Testosterone replacement therapy

testosterone replacement therapy

Testosterone Therapy

Testosterone replacement therapy is a hormone replacement therapy for men to treat hypogonadism or low testosterone levels. Men typically use testosterone therapy for symptoms such as low libido, depressed mood and decreased energy levels.

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What Is Testosterone Therapy?

The U.S. Food and Drug Administration (FDA) approved testosterone therapy for men who want to address hypogonadism and low testosterone. Hypogonadism is when the body does not produce enough testosterone, and it occurs in 19% of men in their 60s. The rates increase for men in their 70s (28%) and 80s (49%).

The popularity of testosterone therapy rose from 2000 to 2013, when a multitude of the hormone products came to market. More than 2 million Americans took testosterone products, including older men using it to improve libido.

The FDA later warned men about the dangerous side effects of these products, including cardiac events. Although testosterone therapy remains popular, concerns about side effects may ultimately reduce demand.

How Does Hormone Therapy Work?

Your body has androgen receptors in tissues throughout your body that help your body use hormones for different important functions. These receptors in tissues from reproductive organs to the brain all respond to increased testosterone taken orally, through injections or through the skin in patches, gels and creams.

When you start testosterone therapy, the hormone produces increased muscle mass, more body hair and increased sex drive. Some effects of TRT can be felt within weeks, while others build over the course of months.

Types of Testosterone Products

Testosterone, as a Schedule III drug, is available only with a prescription. Although there are many supplements claiming to boost testosterone, these over-the-counter products do not contain testosterone and lack any peer reviewed evidence of effectiveness.

Gels (Androgel and Testim)

Testosterone gel is a prescription medication applied directly to a man’s skin. It can be applied to the shoulders, upper arms and abdomen, depending on the brand.

Testosterone gel can unintentionally transfer from your body to another’s with skin to skin contact. This can potentially lead to serious health reactions for the other person.

To avoid this type of gel transfer, apply it to clean, dry and intact skin that clothing can cover. Wash your hands right away with soap and water after applying. Once the gel has dried, cover the area with clothing and keep it covered until you have washed it well or showered.

Injections (Depo-Testosterone)

First approved in 1979, Depo-testosterone is one of the older drugs of its kind on the market. It’s a liquid designed for injection deep into the gluteal muscle.

The active ingredient, testosterone cypionate, is a powder mixed with other ingredients to make a solution. The drug is available in two strengths, 100 mg and 200 mg.

Patches (Androderm)

Testosterone transdermal patches, including Androderm, come as patches to apply to the skin. Patches work best when applied around the same time each night and are left in place for 24 hours. Testosterone patches are worn at all times until replaced with new patches.

Androderm patches should be changed every 24 hours. The old patch should be removed before applying the new one. You should apply the patches to different spots each night and wait at least seven days before re-using a spot.

Capsules (Methyltestosterone and Android)

Combined estrogen-methyltestosterone capsules have been discontinued. They were used to treat delayed puberty in men and boys and breast cancer in women.

Methyltestosterone, an artificial form of testosterone, alone is still available – in capsule and tablet form. It can affect bone growth in boys who are treated for delayed puberty.

Boosters (Testofen)

Testosterone boosters are not testosterone therapeutics. These are supplements with very little evidence to support their use.

Despite insufficient scientific data to support claims, manufacturers have suggested their products increase muscle mass, strength and sex drive in men. Among the most popular testosterone boosters are products containing Tribulus terrestris, DHEA, zinc and d-aspartic acid.

These ingredients have been associated with several side effects, including aggressiveness, breast enlargement, cholesterol changes, prostate problems and an increased risk of cardiovascular disease.

Why Men Use Testosterone Therapy

Men opt for testosterone replacement therapy to counteract a condition of low testosterone, often referred to as “Low T.” For many men, levels of this hormone decrease with age, leading to erectile dysfunction, low libido, loss of body mass and muscle, anemia and depressive moods.

Men turn to testosterone therapy to increase muscle tone, sexual desire and sexual performance, resulting increased confidence as they grow older.

Treating Low T

The FDA approved testosterone as replacement therapy only for men who have low testosterone levels from disorders that cause hypogonadism. Testosterone levels in men usually decline after age 30.

Other causes of Low T include an injury to the testicles, cancer treatments, chronic diseases and stress. Lack of this key sex hormone can also cause health issues, including osteoporosis, loss of muscle mass and strength (sarcopenia) and psychological symptoms. Doctors prescribe testosterone drugs to treat these symptoms.

Remedying Erectile Dysfunction

As men age, erectile dysfunction (ED), the inability to get or maintain an erection, is common. Before Pfizer released Viagra in 1998 as a medication for ED, doctors often turned to testosterone as a treatment.

However, only about 5% of men experience ED because of Low T. Low testosterone levels can contribute to ED but are more likely to reduce sexual desire than cause the condition.

Enhancing Physical Performance

Testosterone therapy can enhance athletic and physical performance. Athletes use it to boost strength and stamina, but it can also help men with chronic fatigue syndrome or fibromyalgia.

The National Football League (NFL) in 2011 banned players’ use of testosterone except for extraordinary health circumstances because of its ability to increase strength and muscle mass.

Benefits of Testosterone Therapy

For many men, the biggest benefit of testosterone therapy is an improved sex drive. But there are other benefits related to muscle growth and body mass, which high-performance athletes and physical trainers acknowledge.

  • Increased libido: Testosterone enhances sex drive, making it especially popular among for men older than 50.
  • Boosted energy level: Testosterone levels decline with age, leading to fatigue and exhaustion. Testosterone therapy can boost energy levels.
  • Increased muscle building: Testosterone increases muscle mass beyond the results possible from a typical workout regimen alone.
  • Better memory: Higher testosterone levels have been associated with improved recall.

While some men report experiencing benefits shortly after beginning treatment, most studies indicate results take weeks or months.

Risks of Testosterone Therapy

Because it involves a potent hormone, testosterone therapy carries a handful of risk factors. Some are common while others are rare. Not all are serious, but anyone who undergoes therapy should be aware of the potential life-changing side effects.

  • Worsening sleep apnea: Some research suggests testosterone therapy can intensify sleep apnea, a disorder in which you temporarily stop breathing while asleep.
  • Acne and skin reactions: Some men experience skin breakouts and severe acne after beginning a cycle of testosterone. You can treat these side effects with anti-inflammatory medications or changing the dosage.
  • Noncancerous prostate growth: Testosterone therapy has long been linked with enlarged prostates in men, which often affects the ability to empty the bladder successfully. In rare instances, benign prostate growths can lead to more serious issues such as prostate cancer.
  • Polycythemia: This is a condition of having too many red blood cells, thickening the blood. If chronic, the condition is called polycythemia vera, or leukemia.

Recent studies had mixed findings about links between testosterone replacement therapy and increased risks of obesity, diabetes and metabolic syndrome. Research linking it to an increased risk of cardiac events is still a source of debate, and studies continue to examine long-term cardiovascular risks.

Heart Attacks and Cardiovascular Side Effects

Multiple research studies tie high concentrations of testosterone products to an increase in heart failure events, though there is some debate. Some scientists suspect it may be related to elevated blood pressure.

The FDA in 2014 warned against using testosterone therapy for age-related low T, noting the therapy requires more study. An ongoing testosterone replacement therapy trial related to the testosterone and heart-related side effects is scheduled to conclude in late 2022.

Dangers to Women and Children

The FDA approved testosterone products only for men with low testosterone levels. Children should never be exposed to testosterone products because they can cause premature puberty and health problems such as liver damage.

Women can inadvertently and dangerously raise their testosterone through skin to skin contact with a man undergoing treatment. Most exposures happen with the gel and cream forms of TRT. When women are exposed to testosterone they may also experience increased hair growth on her face and body, a deeper voice and increased muscle mass.

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Editors carefully fact-check all Drugwatch content for accuracy and quality.

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We only gather information from credible sources. This includes peer-reviewed medical journals, reputable media outlets, government reports, court records and interviews with qualified experts.

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Our team includes experienced medical writers, award-winning journalists, researchers and certified medical and legal experts. Drugwatch.com is HONCode (Health On the Net Foundation) certified. This means the high-quality information we provide comes from credible sources, such as peer-reviewed medical journals and expert interviews.

The information on Drugwatch.com has been medically and legally reviewed by more than 30 expert contributors, including doctors, pharmacists, lawyers, patient advocates and other health care professionals. Our writers are members of professional associations, including American Medical Writers Association, American Bar Association, The Alliance of Professional Health Advocates and International Society for Medical Publication Professionals.

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  1. Dosage 40.5 mg (daily – Androgel 1.62%), 50 mg (daily – Androgel 1%), 50 mg (daily – Testim), 4 mg or 5 mg (daily – Androderm), 50-400 mg (every two to four weeks – Depo-Testosterone)
  2. Used to Treat Hypogonadism
  3. Interactions Insulin, anticoagulants (medicines that decrease blood clotting), corticosteroids; propranolol
  4. Manufacturer AbbVie and Abbott Laboratories; Pfizer & others
  5. Black Box Warnings Virilization
  6. Active Ingredient Testosterone
  7. Administration Route Oral, injection, nasal
  8. Dosage Form Capsule, injection, gel
  9. Drug Class Androgens and anabolic steroids
  10. Is Available Generically True
  11. Is Proprietary False
  12. RxCUI 10379

Michael Swank, Ph.D., is an experienced researcher at the University of Texas Health Science Center. He has an extensive background in neuroscience and cancer biology. Swank’s research has focused on: Psychological and neuroscientific study of public attitudes about virtual health Treatment pathways for…

40 Cited Research Articles

Drugwatch.com writers follow rigorous sourcing guidelines and cite only trustworthy sources of information, including peer-reviewed journals, court records, academic organizations, highly regarded nonprofit organizations, government reports and interviews with qualified experts. Review our editorial policy to learn more about our process for producing accurate, current and balanced content.

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What does testosterone do to a man?

what does testosterone do to a man?

Does testosterone increase sex drive? The relationship explained

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

Testosterone could use a new publicist. Over the years, it’s become shorthand for some less-than-desirable “male” personality traits—aggression, violence, the inexplicable popularity of Nickelback. But the truth is, all people have testosterone, but it is present in much higher levels in men. Testosterone is vital and indispensable to several bodily processes, including sex drive.

So if you experience low testosterone (low T) or low libido, you may wonder—does testosterone increase sex drive? The connection isn’t entirely clear, but research shows that men with low testosterone are likelier to have a low sex drive. Continue reading to learn more.

Created by doctors, backed by science.

Created by doctors, backed by science.

What is testosterone?

Testosterone is an essential sex hormone for both men and women, but men have way more of it. It’s mostly produced in the testicles in response to signals from the pituitary gland; some testosterone is also made in the adrenal glands, which sit on top of each kidney. Along with DHT (another hormone synthesized from testosterone), testosterone is responsible for the physical changes that occur in males during puberty, including secondary sexual characteristics like pubic hair growth, muscle growth, and sperm production (Nassar, 2021).

In men, testosterone plays a significant role in (Nassar, 2021):

  • Libido
  • Erectile function
  • Sperm production
  • Bone density and muscle mass
  • Red blood cell production
  • Growth of facial and body hair
  • Mood

Does testosterone increase sex drive?

Testosterone is one of the hormones that physiologically stimulate the male sex drive. How does it do that, exactly? Researchers aren’t sure, but they’ve found that reduced libido is one of the most common symptoms of low testosterone levels (low T).

As part of the Massachusetts Male Aging Study (MMAS), researchers spoke with over 1,500 men about their sex drive, then measured their testosterone levels. The study found that the men who reported lower sexual desire had a higher chance of having low T (Travison, 2006).

What are normal testosterone levels?

Low testosterone and sex

Low T, also known as hypogonadism, is an abnormally low level of testosterone in the blood, usually defined as measuring less than 300 ng/dL (nanograms per deciliter). Normal testosterone levels are typically between 300 and 1,000 ng/dL, depending on who you ask. Keep in mind that low testosterone levels are just one part of the diagnosis of low T. Symptoms and signs of low testosterone also play a role, and some experts will recommend treatment even if T levels are slightly higher than 300 ng/dL, but the symptoms and signs are typical of low T.

Testosterone levels naturally decline with age. The decrease begins around age 30 and continues to drop about 1% each year. The pituitary gland sends fewer messages to the testes to produce testosterone, and the testes obey. Meanwhile, a protein called sex hormone-binding globulin (SHBG) increases in men as they age. All of this reduces the body’s active (“free”) form of testosterone.

Because T affects many bodily systems, low testosterone levels can cause many symptoms, including fatigue, loss of muscle mass, increased body fat, and anemia (low red blood cell count).

Related to sex life, low testosterone can cause:

Many people who experience low testosterone can resolve their symptoms with testosterone replacement therapy (TRT). However, not everyone is a candidate for TRT, and other treatments are available, such as clomiphene, a drug that can be used off-label to treat low T in men. A healthcare provider can help you create a safe treatment plan for low T.

Sexual dysfunction: what is it, causes, treatments

Does low testosterone cause ED?

Low testosterone is one health condition that can cause erectile dysfunction (ED). Other health conditions that can cause ED include (McMahon 2019):

Other causes of erectile dysfunction include certain medications like SSRIs, depression, anxiety, substance abuse, and lifestyle factors like lack of exercise (Irwin, 2019; Wang, 2018).

How to test for low testosterone

A healthcare provider can measure your testosterone levels with a blood test. T levels are usually highest in the morning and vary throughout the day. So, to diagnose low T, your healthcare provider may require two early-morning tests (usually between 7 and 9 a.m.) on different days to be low (< 300 ng/dL).

What is TRT?

Testosterone replacement therapy (TRT) is an FDA-approved treatment to increase testosterone and treat the symptoms of low testosterone. In essence, TRT gives your body the testosterone it isn’t producing. Testosterone therapy can be administered in several different ways, including (Bhasin, 2018):

What is libido and how does it relate to sex drive?

A common side effect of testosterone replacement therapy is low sperm count. Artificial testosterone can cause your body to slow the production of sex hormones because it thinks you’re making enough. This may slow sperm production and worsen your body’s ability to make its own testosterone, which could make you dependent on continued TRT (Osterberg, 2014). Because Clomid doesn’t dull testosterone production like TRT, it maintains male fertility and can be an option for men who don’t want the side effects of TRT (Krzastek, 2019).

Other side effects of TRT can include acne, enlarged prostate, enlarged breasts, lower fertility, and worsening sleep apnea.

If you experience a chronically low sex drive or reduced sexual function, make an appointment with your healthcare provider. They can perform a blood test, evaluate you for other conditions that might cause your symptoms, and, if appropriate, prescribe a testosterone-boosting treatment that’s right for you.

References

  1. Bhasin, S., Brito, J. P., Cunningham, G. R., et al. (2018). Testosterone therapy in men with hypogonadism: an Endocrine Society clinical practice guideline. The Journal of Clinical Endocrinology and Metabolism, 103(5), 1715–1744. doi:10.1210/jc.2018-00229. Retrieved from https://pubmed.ncbi.nlm.nih.gov/29562364/
  2. Irwin, G. & Mayans, L. (2019). Urology, an issue of primary care: Clinics in office practice. Elsevier. Retrieved from https://www.elsevier.com/books/urology-an-issue-of-primary-care-clinics-in-office-practice/irwin/978-0-323-67807-0
  3. Krzastek, S. C., Sharma, D., Abdullah, N., et al. (2019). Long-term safety and efficacy of clomiphene citrate for the treatment of hypogonadism. The Journal of Urology, 202(5), 1029–1035. doi:10.1097/JU.0000000000000396. Retrieved from https://pubmed.ncbi.nlm.nih.gov/31216250/
  4. McMahon, C. G. (2019). Current diagnosis and management of erectile dysfunction. Medical Journal of Australia, 210(10):469-476. doi:10.5694/mja2.50167. Retrieved from https://pubmed.ncbi.nlm.nih.gov/31099420/
  5. Nassar, G. N. & Leslie, S. W. (2021). Physiology, testosterone. StatPearls. Retrieved on Jan. 6, 2022 from https://www.ncbi.nlm.nih.gov/books/NBK526128/
  6. Osterberg, E. C., Bernie, A. M., & Ramasamy, R. (2014). Risks of testosterone replacement therapy in men. Indian Journal of Urology: IJU: Journal of the Urological Society of India, 30(1), 2–7. doi:10.4103/0970-1591.124197. Retrieved from https://www.indianjurol.com/article.asp?issn=0970-1591;year=2014;volume=30;issue=1;spage=2;epage=7;aulast=Osterberg
  7. Travison, G. T., Morley, E. J., Araujo, A. B., et al. (2006). Relationship between libido and testosterone levels in aging men. The Journal of Clinical Endocrinology & Metabolism, 91(7): 2509–2513. doi:10.1210/jc.2005-2508. Retrieved from https://academic.oup.com/jcem/article/91/7/2509/2656285
  8. Wang, X. M., Bai, Y. J., Yang, Y. B., et al. (2018). Alcohol intake and risk of erectile dysfunction: a dose–response meta-analysis of observational studies. International Journal of Impotence Research, 30(6), 342–351. doi:10.1038/s41443-018-0022-x. Retrieved from https://pubmed.ncbi.nlm.nih.gov/30232467/

Felix Gussone is a physician, health journalist and a Manager, Medical Content & Education at Ro.

Normal testosterone levels

normal testosterone levels

What Are Normal Testosterone Levels?

Testosterone is a hormone, which is a substance in the body that acts as a chemical messenger. Hormones are made in one part of your body and then travel to other areas to help control how cells and organs work. Testosterone is important for your body to function properly. High or low testosterone levels can lead to unwelcome symptoms.

Fortunately, it’s easy to find out if your testosterone levels are in the normal range. This article discusses normal testosterone levels, tests, and treatment.

What Is Testosterone?

Testosterone is an androgen hormone that’s produced by the adrenal cortex , the testes , and the ovaries .

The endocrine glands make hormones. Men produce hormones in their testes, and women make them in their ovaries.

Testosterone and estrogen are two of the most well-known hormones. Though testosterone is typically recognized as the “male hormone” and estrogen is often referred to as the “female hormone,” they’re both found in both men and women. Both men and women can experience health problems if their testosterone levels are out of the normal range.

Different Types of Hormones

Researchers have identified about 50 different hormones in the human body, which control various processes, such as hunger, mood, sexual function, metabolism, growth, and menstrual cycles.

Normal Testosterone Levels

Under normal circumstances, testosterone performs many important functions in your body.

In men, the hormone plays a key role in:

  • Sex drive
  • Sperm production
  • Muscle and bone growth
  • Deepening of the voice and hair growth
  • The development of male sex organs
  • Mood

Generally, healthcare providers consider normal testosterone levels in men to be between 300 and 1,000 nanograms per deciliter (ng/dL). These ranges may vary slightly depending on the criteria used by your provider or laboratory.

Your testosterone levels may be higher or lower based on your age, sex, medications you take, and other health conditions you have.

Testosterone production tends to slow as a person ages.

Testosterone in Women

Though women produce less testosterone than men, the hormone still plays a vital role in how a woman’s body functions.

A normal level of testosterone in women is considered to be between 15-70 ng/dL.

Testosterone Levels in Men vs. Women

Normal testosterone levels are usually described as:

Men typically produce the most testosterone during their teenage years.

Symptoms of High or Low Testosterone

You might start to notice changes if your testosterone levels become too high or low.

Symptoms of High Testosterone in Men

Having too much testosterone isn’t a common problem for men. However, males who do have too much testosterone may experience:

  • Low sperm counts
  • Prostate enlargement
  • Heart muscle damage
  • Liver disease
  • Acne
  • Weight gain
  • High blood pressure or high cholesterol
  • Fluid retention
  • Stunted growth (in teens)
  • Aggressive behavior or mood swings
  • Headaches
  • Increased muscle mass
  • Higher risk of blood clots

Symptoms of Low Testosterone in Men

Low testosterone is more common among men. This condition may cause the following symptoms:

  • Breast enlargement
  • Low sex drive
  • Trouble getting an erection
  • Low sperm count
  • Fertility issues
  • Bone weakness
  • Irritability or trouble concentrating
  • Hair loss
  • Depression
  • Loss of muscle mass
  • Fatigue
  • Hot flashes

Symptoms of High Testosterone in Women

The correct balance between testosterone and estrogen is crucial for a woman’s ovaries to work properly.

Women with too much testosterone may experience a deep voice or a decrease in breast size.

One of the most common causes of high testosterone in women is a condition called polycystic ovary syndrome (PCOS), which is characterized by enlarged ovaries with small cysts.

Symptoms of high testosterone in women may include:

  • Infertility
  • Acne
  • Irregular periods
  • Obesity
  • Blood sugar issues
  • Extra hair growth
  • Male-pattern baldness
  • Depression or anxiety

Symptoms of Low Testosterone in Women

Women can also have a testosterone deficiency, which may cause:

  • Irregular periods
  • Fertility issues
  • Osteoporosis
  • Low sex drive
  • Vaginal dryness
  • Breast changes
  • Depression or poor concentration

Tests

If your healthcare provider suspects your testosterone levels might be too high or low, they may recommend a blood test to measure the amount of the hormone.

Most of the testosterone in your blood is attached to two proteins, but some testosterone, called free testosterone or bioavailable testosterone, is not attached to proteins.

The two main types of testosterone blood tests are:

  • Total testosterone: This test measures both free testosterone and attached testosterone in the blood.
  • Free testosterone: This test only measures free testosterone.

You’ll likely have the test in the morning (testosterone levels are highest at this time), but because testosterone levels fluctuate throughout the day, you may have to have the blood test more than once to confirm your levels.

Some studies have shown that at-home saliva tests might also be used to accurately measure testosterone levels in the body.

Risks of Testosterone Blood Tests

Risks for a testosterone blood test are minimal but may include:

Treatment

If you and your healthcare provider decide to treat low testosterone levels, you may be a candidate for testosterone replacement therapy (TRT). With this treatment, you are essentially supplementing your body with the testosterone it’s missing.

Testosterone is available in the following forms:

  • Oral capsules, including Kyzatrex, Jatenzo, and Tlando
  • Gel
  • Topical solution
  • Patch
  • Injection
  • Implantable pellet (implanted under the skin)
  • Intranasal gel (in the nose)

Your healthcare provider can help you determine which formulation of testosterone is most suitable for you.

Recent studies have shown that the use of TRT is increasing, and more than half of prescriptions for testosterone are written by primary healthcare providers.

Treatments for high testosterone levels may include lifestyle changes, including exercise to improve symptoms. Healthcare providers may also prescribe antiandrogen medications like Aldactone ( spironolactone ), diabetes drugs like Actos ( pioglitazone ), or oral contraceptives to help lower testosterone levels or relieve symptoms of high testosterone.

Risks of Testosterone Therapy

Some risks and side effects of TRT include:

  • Possible risk for heart problems, cancer, and blood clots (though recent studies show that the risk for all of these is low or possibly not risky at all)
  • Infertility
  • Side effects such as breast enlargement (in males), skin reactions, changes in hair patterns, acne, and back pain

Summary

Testosterone is an important hormone for both men and women. If your testosterone levels are too low or high, you might develop symptoms that interfere with your daily life. A simple blood test can help you determine if your levels are in the normal range, which are 300–1,000 ng/dL for men and 15–70 ng/dL for women. Treatments are available if your testosterone levels are abnormal.

A Word From Verywell

If you feel like your testosterone levels might be too high or too low, talk to your healthcare provider. They can help you decide if a blood test is warranted. If you need treatment, your provider can also help you understand the risks and benefits of different therapies.

Frequently Asked Questions

Taking testosterone replacement therapy is a common way to increase testosterone levels. However, this treatment can also cause side effects, so it’s important to talk to your healthcare provider about the risks.

An estrogen blocker is a therapy that keeps your body from making or using estrogen. You should always talk to your healthcare provider before combining any types of medicines, including an estrogen blocker and testosterone.

Some research has shown that certain lifestyle habits may help boost testosterone levels. Exercise, particularly weight-lifting, is one way to increase levels. Other studies have found eating a healthy diet, minimizing stress, and getting enough sleep can increase testosterone levels or help normalize hormone levels.

Testosterone is made in your body. It’s produced by the adrenal cortex, a man’s testicles, and a woman’s ovaries.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

  1. Nemours Children’s Health. Definition: hormones.
  2. University of Rochester Medical Center. Total testosterone.
  3. Tulane University. Endocrine system: types of hormones.
  4. Mount Sinai. Testosterone.
  5. Harvard Health. Testosterone – what it does and doesn’t do.
  6. MedlinePlus. Testosterone levels test.
  7. Keevil B, MacDonald P, Macdowall W, Lee D, Wu F. Salivary testosterone measurement by liquid chromatography tandem mass spectrometry in adult males and females. Ann Clin Biochem. 2014;51(Pt 3):368-378. doi:10.1177/0004563213506412
  8. Petering RC, Brooks NA. Testosterone therapy: review of clinical applications. AFP. 2017;96(7):441-449.
  9. Hunter MH, Carek PJ. Evaluation and treatment of women with hirsutism. AFP. 2003;67(12):2565-2572.
  10. Kraemer WJ, Staron RS, Hagerman FC, et al. The effects of short-term resistance training on endocrine function in men and women. Eur J Appl Physiol Occup Physiol. 1998;78(1):69-76. doi:10.1007/s004210050389
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Men’s testosterone

men’s testosterone

102: Men’s Health Essentials — Testosterone

Seems like every ad you see these days has some new claim about testosterone. It’ll give you energy, build muscle, keep you young, and so on. But is any of that true? John Smith, MD, give the guys the lowdown on testosterone replacement therapy and what it can actually do for men with low levels of the hormone.

Episode Transcript

This content was originally created for audio. Some elements such as tone, sound effects, and music can be hard to translate to text. As such, the following is a summary of the episode and has been edited for clarity. For the full experience, we encourage you to subscribe and listen— it’s more fun that way.

Scot: So will testosterone solve all my problems as a man? That’s today on “Who Cares About Men’s Health,” providing information, inspiration, and a different interpretation about men in men’s health. He brings the MD to the show. Ladies and gentlemen, Dr. Troy Madsen.

Troy: Yeah. Ready to talk about testosterone. I am curious, very curious. Where do we go with this? What do we do?

Scot: Offsetting the MD, I bring the BS. My name is Scot Singpiel. And Mitch, he’s responsible for bringing the microphones. Welcome, Mitch.

Scot: I think Mitch needs some testosterone. You know how low key he is.

Mitch: It’s low T day. I mean, based on everything I see on the internet, that’s got to be what’s going on.

Scot: Well, yeah. I mean, you go to the internet . . . I’m going to do my impersonation of the internet. You ready for this?

Scot: All right. You’re, like, “You have low energy? You’ve got to get some T. You putting on a few pounds of fat? You’ve got to get some T. You having trouble sleeping? You’ve got to get some T.” That’s my impersonation of the internet. It’s the answer to everything.

Scot: Yeah. So we’re going to find out if that is actually true or not with Dr. John Smith.

So, Dr. Smith, what is the common complaint you get when somebody comes to you and they’re interested in testosterone treatments? What problem are they trying to solve? What are they trying to cure? All the things I talked about? Something else?

Dr. Smith: Absolutely. I mean, I think the thing about testosterone is the symptoms are so wide-reaching — fatigue, cognition, erectile issues. They’ve heard on the internet, or they’ve talked to a friend who’s on testosterone, and they’re like, “Man, it just changed my life. It fixed everything.” Which in some people’s cases that may be true, but for most people, it definitely can play a role in helping them out, but I don’t think it’s the cure-all that you’re talking about, that the internet shows. It’s not making Frank Thomas who he is today.

Scot: And that’s dangerous, right? Because you can get testosterone without even having a face-to-face conversation with a doctor, right? You can essentially just order it online. Is that true or is that overstated?

Dr. Smith: I think some of the newer companies you’ve got out there that are making things available . . . hopefully you’re getting at least a video conferencing going over your medical history with someone who’s a medical provider, whether it be a nurse practitioner, a PA. Hopefully you’re talking with a physician. If they’re not doing it that way, they’re doing it wrong.

But testosterone is one of those things where it can be very helpful. I have quite a few patients that are on it, and I think it is one of those things that can definitely benefit people. But the extent that it benefits them kind of varies between patients.

Scot: Testosterone, I get the impression that it’s probably not a do-it-yourself sort of a thing. It’s not something you want to, as a layperson, just dive into on your own. Why is that?

Dr. Smith: Well, there are certain . . . everything has a risk and a benefit, and testosterone is no different. For people who have low testosterone, replacing it can really make a difference. It can give you that increased boost of energy, help you with weight loss, help you with metabolism, help with sleep. It can help with erections. I mean, it can help with cognition in people who have low testosterone. However, it’s not necessarily the thing that’s going to fix all those problems.

And oftentimes I’ll go through people’s history and say, “Hey, man, your testosterone is normal. Adding more to the mix isn’t likely to fix things. We should look at other issues.” And so I think really just taking that deep dive and seeing if it’s something that is right for you is important.

Troy: I guess, John, I’ve seen all this stuff Scot mentioned, you see all these things on the internet, you see TV ads, etc. Yeah, I think I wonder myself, “Man, is my testosterone low? Should I be worried about this?” At what point do you tell people, “You should get your testosterone level checked”?

Dr. Smith: I think if you’ve looked at some of the other . . . if you’ve talked to your primary doctor and kind of gone over things, the usual suspects of a thyroid issue or vitamin deficiencies, things like that that they check a lot, if those are all normal, I think it’s completely reasonable to look at it.

Some people say, “Oh, well, my dad had low testosterone and I got it checked in my 30s.” But if you look at the facts of the matter, about 40% of people over the age of 45 have a testosterone level of 300 or less. And so that’s a decent amount of the population that’s out there. And so I think if you have an interest in it, it’s okay to ask to have it checked because it’s better to know and to at least know what your options are where it may be a benefit to you.

Dr. Smith: So your regular doctor can check it. You can make an appointment with a men’s health specialist like we have at the University of Utah. We have a men’s health group with multiple different providers. We have nurse practitioners, PAs, and multiple MDs and DOs that can take care of your needs as far as checking the hormones. But that’s the first thing that we do.

And hormones, ideally, should be checked before 10:30 in the morning because our bodies spike testosterone between the early hours of the morning. Usually people will say between 4:00 a.m. and 10:00 a.m. in the morning. And so we want to check it to see what your body is actually doing.

If you’re low in the morning, the odds are that you’re high in the afternoon are going to be really slim to zero because your body spikes it in the morning to give you that boost of the hormones that you need to get you through the day.

Scot: And when you take a look at that test, it’s a range, right? So a man gets the test done and you’ve got some numbers and there’s a range. And what does that tell you? Let’s pretend I’m at the low end of the range, but I’m still considered normal. Is that somebody that you would suggest testosterone therapy for?

Dr. Smith: I think a lot of it is the discussion that you have with the patient. So the range is huge too. If you look at the range, most labs are between 300 and 1,000. Some are a little less, some are a little more, but just for intents and purposes of this discussion, about 300 to 1,000.

So let’s say, Scot, you’re at 350. Well, what does that mean? Insurance requirements say that we’ve got to get two tests that show a low value before 10:30 in the morning. So let’s say we’ve done that. You come in, your first one was 350, your second one was 340 or 338. What do we do from there? Well, then we have a discussion.

And I think in a lot of those folks, it is reasonable to discuss therapy. People outside the normal range, it’s obviously okay to discuss that as well, but people tend to feel better in a range around 400 to 700. Sometimes, some people will say 600 or higher. There’s a lot of different variability out there between who you talk to about it.

But again, if you’re feeling the symptoms of fatigue, decreased libido, decreased erectile quality, some of those things are really hitting you hard, and you’re like, “I’d love to try testosterone to see if it would help some of those symptoms,” I think it’s completely reasonable to do that.

Mitch: But insurance won’t cover it unless you are beneath that range?

Dr. Smith: Not necessarily. Insurance wants to see that you’re in the low. Really, I think it’s reasonable for anybody that’s 350, 400, and below. You can talk to them about testosterone replacement therapy. And if there’s benefit there, insurance usually won’t balk at it. And if they do, and it is helping you, cash pay for this stuff is not obscene.

Mitch: I’ll just disclose. Now, I had my testosterone levels checked after we did a previous episode, and my number is right around 400. And my primary care provider is like, “Oh, no, you don’t need to. We don’t need to. There’s no need to talk about testosterone therapy.” And so I’ve kind of put it in the back of my mind.

But then at the same time, you have the weird people on the internet that they say you need to be 600 or 1,000 or above to be healthy. And it’s just like if I’m right there, I’m at the 400, maybe it would be helpful. What would you say to someone in my situation?

Dr. Smith: I think you’ve got to look at the whole picture, but I think it’s definitely something that you could consider. Again, most primary care doctors don’t do a lot of hormone replacement, so they’re going to say, “Hey, you’re well within normal range. We’re not going to touch it. We’re not going to do anything,” because that’s their comfort zone.

This is the thing that I do every single day where I get people sent from their primary care doctor to talk about this stuff. And I think it’s an in-depth conversation of, “Hey, let’s look at the whole picture. Is there anything else going on that’s a problem, or could be seen as a problem? Do you have a thyroid issue? What is your BMI? How does your weight look? What’s your exercise routine?” and things like that, because those things can be done before supplementing testosterone.

And there are some interesting numbers out there with diet and exercise. If people will lose weight of 10 pounds or so, you can increase your testosterone by 100 points by losing 25 pounds and getting diet and exercise.

But a lot of times, it’s hard to get the motivation to go do diet and exercise when you’re overweight and you’re really lethargic. And so it’s like, “Would testosterone help me get there?” and a lot of those things as well.

And so again, exercise 15 minutes a day for 6 months of moderate intensity exercise will increase your testosterone by 22 points. And then if you’re exercising for 30 to 40 minutes a day, you’ll increase it by 50 to 60 points. And so again, there are things you can do other than testosterone if you’re kind of in that range, and any of those things fit.

Now, Mitch, I know you’re super fit, so that doesn’t really . . .

Dr. Smith: . . . matter for you. But if those are things that you can do, those are modifiable things you can do in your life to increase your testosterone naturally.

Troy: You mentioned diet also, John. I mean, it sounded like we’re talking more about weight loss here, but are there any kind of dietary changes in terms of foods you’re eating or foods you can eat or even supplements that would increase your testosterone levels without actually having to go for any sort of hormone replacement therapy?

Dr. Smith: You’ve seen Gascon in “Beauty and the Beast.” That’s how he got so huge.

Dr. Smith: There are no real big things that are out there that are known to necessarily just be super beneficial, other than eating as clean as you can.

Testosterone is a hormone and hormones are built on a backbone of cholesterol, so they’re kind of fat. They’re built on fat. And so when you have excess fat tissue, sometimes the hormones like to hang out there because they don’t love water. And so you’ll find that people may have a higher testosterone level when they lose that body weight, because now they don’t have as much body fat and that testosterone is able to kind of circulate. Plus, you’re in better health and your body is able to just do what it does better.

Troy: Speaking of our concerns . . . obviously, Mitch has thought about it. I’ve thought about it. I know, Scot, you’ve told us before you’ve had your testosterone level checked. I think a lot of men wonder about this, and I think we get concerned and we say, “Hey, maybe I don’t have a lot of energy,” whatever it might be. Of those who come in to get tested, what percent really have low testosterone?

Dr. Smith: I mean, my practice is kind of skewed, because by the time a lot of these guys get to me, they’ve already had it checked with their primary doctor who’s not going to treat them unless they’re outside of the normal range. And then when they are, they get referred to our office. A lot of primary care doctors don’t love treating testosterone patients and they know that that’s kind of what we do.

And so I get a skewed percentage. Most of the people who come in and are looking for testosterone have already kind of been pre-screened, so they are low. I would say a vast majority, at least three-quarters of the people that I see, already have testosterone levels that come back and are low and they’re there to talk about therapy as a referral from their primary doctor.

Troy: Interesting. Yeah, I just wondered if it’s one of these things that it’s just something else for us to worry about. And if a lot of us are getting tested and it’s a small percentage, or maybe it is, like you said, over 45% . . . I think you mentioned 45% of men have levels under 300. So maybe more of us should be getting tested at some point and we’re just not getting tested.

Dr. Smith: Yeah. It’s around 40% over the age of 45, you’ll see low testosterone levels. And again, it’s one of those things where you tend to hit that middle age, people tend to not necessarily be as active, and things like that as well. So there are a lot of things that go into it.

But if we’re looking at the actual testosterone itself . . . Let’s say you come in, you’re low or you’re low normal, and you want to try testosterone. There are a lot of things you need to have a discussion with the patients about. Are you interested in having children in the future or any more children if you already have children? What are your goals as far as that goes?

There are multiple different ways to treat testosterone these days or to treat low testosterone, I should say. And kind of having that full disclosure discussion with the patient goes a long way, because there are multiple different modalities of treating it from oral medications to topical medications, to injections, to long-term injectables, to subcutaneous pellets. I mean, there’s a myriad of different treatment options that we can discuss.

Scot: And of your patients that you start on therapy, you mentioned that the symptoms can be very broad and caused by a lot of different things. Maybe you’re not getting enough sleep. Maybe you’ve got too much stress in your life. That’s why you’re low energy. Maybe you’re not eating the right foods or exercising. That’s why you don’t feel good. How many after they get testosterone that come in that have low testosterone actually go, “Yeah, that made a difference,” versus, “I’m about the same”?

Dr. Smith: Majority of them. But that also varies via the root that they get testosterone. So I’ll talk kind of a little bit about each modality. Oral options is . . . there’s a medication called Clomid. A lot of people know it as a fertility medication. Women use it for fertility purposes. But what the medication does is it stimulates your body to produce more testosterone and more sperm. This is a very gradual improvement in testosterone. And a lot of times people don’t feel that robust boom, that jolt of energy and things, because it’s kind of a low-key slow rise of the testosterone back into the normal range. They don’t have that big boost.

And most of the time, when people have that boost, it’s from the injection because they’re injecting a bolus of testosterone that then is being absorbed into the body and they have their levels shoot outside the normal range. So they feel like Superman. It gives them that rush of testosterone, which you don’t get with topicals, the lotions, and you don’t get with the oral because it’s doing what your body normally did before you didn’t create enough testosterone. And so you don’t get those super highs that you would have before.

So a lot of patients know, “Oh, man, I do have more energy. I do feel good.” The ones who do injections tend to come back and have more of a, “Man, that’s great. This stuff is great,” because they get that boom, that rush, that spike of testosterone very quickly.

Troy: And then how long until that wears off?

Dr. Smith: So usually people inject on a weekly basis, sometimes every other week, depending on their injection tolerance. And I do have a few patients who inject multiple times per week of low doses because they don’t like that roller coaster effect. You do really get a high of testosterone and then it kind of fades out over the course until you do your next injection.

And so that’s what they notice. They’re like, “Man, I just get this high, and I feel it for about two to three days, and then it kind of wears down and I feel pretty good. And then when I do my next injection, I get that high again.” I see that a lot more frequently with people who inject testosterone rather than take oral medications or do topical gels.

Scot: And what about side effects or downsides to testosterone therapy?

Dr. Smith: Man, it’s almost like you wrote a script for that or something.

Troy: Talked about the good stuff. Let’s talk about the bad stuff.

Dr. Smith: I’m going to make you feel like Superman. And now I’m going to tell you the downside.

Scot: Kryptonite is no good for you.

Dr. Smith: Exactly. You really have to monitor things with testosterone. So testosterone can cause an increase in red blood cell mass, and that in and of itself isn’t necessarily a bad thing as long as it doesn’t get outside of the normal range too far. That puts you at an increased risk of a cardiovascular event, like a heart attack or stroke.

Now, those incidents are rare, but it’s something that we definitely keep an eye on. And that’s a reason why we follow these folks with labs regardless of the type of replacement that we do.

Other things that we follow is your estrogen levels can rise because testosterone is a precursor to estrogen. There is a molecule called aromatase that actually converts testosterone to estrogen. Their chemical formula is very, very similar.

Your body likes to keep a ratio of about 10-to-1 testosterone to estrogen, and so the higher your testosterone goes, the higher your estrogen level goes.

And some people will develop breast sensitivity, nipple tenderness, or breast growth from elevated estrogen if their bodies are over-converting to estrogen. And so we watch that closely because that can be bothersome to folks.

And then a couple of the other things, we always monitor PSA in folks that are over the age of 40, or at least I do in my practice because . . . There’s not an increased risk of prostate cancer, but if you were to develop prostate cancer, testosterone would feed the prostate cancer.

It’s kind of like if you have a match and it’s lit, nothing happens. But if you have a match and you pour a gasoline on it, you have a problem on your hands. And so the prostate cancer would represent the match and the testosterone would represent the gasoline. It would help it to kind of progress faster in a way.

And those are the things that we really kind of keep an eye on, especially people with family history or people who have had prostate cancer that we’re treating with testosterone, which yes, we do that quite frequently.

Troy: So now that we’ve talked about the risks of taking the testosterone supplement, let’s just say someone is like, “Okay, I’ve had my testosterone level checked. It’s low. I don’t want to assume those risks.” What’s the downside of that?

Dr. Smith: So the downside is you can develop osteoporosis with time. There are some studies that . . . initially some studies came out with testosterone that said testosterone supplementation caused cardiovascular issues, and now it’s become the opposite. That’s been debunked, and there is some literature out there, I don’t know that it’s super robust, that said low testosterone can increase your risk of cardiovascular events. So those are the big things of not having enough.

Long term, it’s really difficult to assess a lot of those risks, but those are the risks. if you were to just have low testosterone.

Scot: Do you have anybody ever come in that you just are like, “No, it’s not a good idea for you”?

Dr. Smith: Yeah. I mean, people who come in with a testosterone level of 600 from their primary care doctor. It’s a bad idea.

Scot: Yeah. But I mean low testosterone. Is there ever a time where it’s just like, “No, probably not. The risks are too big”?

Dr. Smith: So I think the one thing that I didn’t get to with the risks is testosterone replacement will cause sterilization. It will stop you from being able to have children. When you supplement testosterone . . . not all methods of supplementation will hurt fertility, but injections will. Anything that’s injectable topical or the long-term injectables or pellets all will cause sterility to a point. And so those things are things that you’ve got to have those conversations.

So if someone comes into my office and they have low testosterone and they don’t want to take the pill like Clomid and they’re like, “I just want to do injections, but I still want to have kids in six months,” I would say, “Let’s hold off until you’re done having kids or until your wife gets pregnant, or go donate some sperm so that you can have children if that’s your goal, before we start therapy.”

Scot: Mitch, given the information that you just got today, are you going to go in? You’re going to get some T?

Mitch: I don’t know. I’m in a place where I think that after this conversation, I would like to go talk to a men’s health specialist, especially if there is a hesitation from primary care physicians to just be like, “Oh, you’re in the normal range. You’re good.” There is a curiosity there. There is an interest there, knowing where I’m sitting at on the levels, if they think it would be something that could help with some of the situations that I’m dealing with right now.

Scot: I guess I’m afraid that it just sounds like another pill. I don’t mean that as I don’t want to take drugs. I just mean we’re all looking for the quick fix, right? So yeah, maybe I’m a little tired. Would I like to lose some fat? Sure. Would I like to have a little bit more muscle mass? Yeah. If I’m in that normal range and on the low end, I don’t know. It just feels like I’m expecting too much. I’m going in for the wrong reasons. Does that make sense to anybody?

Dr. Smith: And I don’t think you can necessarily . . . I mean, again, I’m not trying to sell testosterone here. I just think that . . .

Scot: No, that’s not the point of this. We’re just trying to get some information, for sure.

Dr. Smith: Right. But I think that if you want to feel your best and be able to do your thing to the healthiest you can be, I don’t think it’s a bad thing to come in with the desire to be healthier, to feel better, to have more energy. Again, when you start testosterone therapy, you do have a change in lean muscle mass by about five kilograms switch over from body fat to lean muscle.

Scot: Hold on a second. Hey, Siri, convert five kilograms to pounds.

Dr. Smith: It’s 2.2 pounds per kilogram.

Scot: It’s 11 pounds there. All right.

Dr. Smith: Actually, I said that incorrectly. It’s five pounds of fat or two and a half kilograms. My apologies.

Dr. Smith: But still, a five-pound change in your body mass, it can be substantial. It can really help. And again, those are just the numbers that we have from the literature that’s out there. And so it can be beneficial.

I don’t think there’s a wrong reason to come in to look for it. Most patients aren’t coming in to be like, “Hey, man, I saw this magazine with this guy Schwarzenegger on it and he was pretty big. I kind of want to get there. Can you help me?” Those aren’t the patients that I see.

People come in, they’re like, “I’m really fatigued. I feel tired at night. My libido is down. I want to feel better. And I want to see if testosterone may be helpful in that regard.” And they’re not looking necessarily as a magic bullet or trying to use it as a substance of abuse where they can go and just change their whole body composition. But I think it is very beneficial for a lot of people.

Scot: Troy, where do you stand on it?

Troy: As we talk about this, I just feel like there are so many other things I need to address. That’s way down the list. We talk about energy and everything there. I feel like, wow, I’m still trying to figure out how to sleep and those kinds of things. So I’m kind of hung up on that still. We’ve talked about this and if we talk about it today, I am still kind of curious about it, but I don’t think I will be getting tested any time soon. I’ll say that.

Scot: I noticed a parallel from another show that we did. You’re talking about using testosterone treatments to kind of get over that hump, right? Let’s say that you would like to exercise more, but you don’t have the energy and you do find you do have a low testosterone. That was almost kind of like using medication for mental health. If you’re having challenges with your mental health, it can be really hard to become motivated to exercise or eat well, or maybe you don’t even sleep well. So you can take medications for a short period of time until you kind of get those things working. We talk about that Core Four, how they all interact with each other. And then possibly come off of it. Am I understanding that correctly?

Dr. Smith: Yeah. And I think if that’s your plan, you’ve got to look at a way to keep the testicles producing while you do that. If you went to an injectable or a topical testosterone that’s going to shut down the body’s production . . .

So let me nerd out a little bit with the physiology of this. Your body has these precursor hormones called FSH and LH. And those are the two hormones. They are in both men and women. In women, they regulate the menstrual cycle, and in men, they stimulate the testicles to make testosterone and sperm.

And when you give testosterone, it’s a negative feedback loop. And so your body sees there’s enough testosterone in the bloodstream and stops sending FSH and LH to stimulate the testicles. And so you’ve got to do something to keep those testicles producing if you’re going to be on testosterone in the short term. That’s where other drugs come in.

There’s an injectable called HCG that we use to help stimulate. It’s an LH analog, meaning it’s not LH, but it will stimulate the LH receptor on the testicle. And it will continue to have the testicle continue to produce at a lower level, even though you’re giving yourself exogenous testosterone.

And then if you decide to come off after six months or a year or whatever, after you’ve gotten in shape and you’ve gotten that motivation, then you don’t have this complete drop-off of testosterone where your body has to start making it again where it hasn’t for the last year.

Scot: But it would. If you’re using a topical solution that’s telling your body then not to produce more testosterone, does that mean you’re dedicated to that for the rest of your life?

Dr. Smith: You can. Now, you can come off of it. And the thing I tell people is if your body was already not producing enough and you haven’t done a darn thing to change that, your body is not likely going to go back to producing more than it was before you started the drug. But then there’s always that kind of window where your body has to catch up and it’s not producing hardly anything at all and you just feel like garbage.

Troy: But it would come back over time?

Dr. Smith: Yes. And that’s the part where the HCG comes in to help it, where you don’t have as big of a drop-off. Scot: All right. So now I need to ask the question that I think everybody is wondering. I’ve heard that if you’re on testosterone treatments, your testicles get smaller. Is that true?

Scot: Okay. How small are we talking? Yeah.

Troy: What are we talking here? Yeah. Like raisin-size?

Scot: I mean, for running marathons, Troy, that might not be a terrible deal. Right?

Troy: Thanks, Scot. Much less chafing. Yeah.

Dr. Smith: He’s looking out for you, Troy. He’s looking out for you.

Troy: Exactly. It’d just be nice smooth surface down there.

Dr. Smith: You’ll shave minutes off your time.

Troy: Exactly. All that extra weight.

Dr. Smith: Yeah, you won’t have the metronome like you’ve got now, but it’ll work out.

Dr. Smith: But they do shrink, and over time you’ll notice that testicular size loss happens the longer you’re on testosterone. So people who’ve been on, say, long-term injectable testosterone, they’ll shrink down and be very, very small when you get down to it, almost to raisin-like size that you’ll see, which is something that I always talk to people about. And again, that’s where HCG can come in if you want to preserve testicular size.

And to some people, that’s important. And to other people, I say, “If you’re not looking to have kids and it doesn’t really matter to you . . .” I’ve never, ever in my experience of having this had someone come in with their spouse and had them saying, “Man, you know what? I just wish Troy’s balls were bigger.”

So I don’t know how much it really matters, but I think a lot of times it is kind of the vanity side of it, of, “This is what I know, this is what I’ve had my whole life, and I don’t want it to change.”

Troy: Well, I will tell you, John, hearing that, I’m reassured that your patients are not talking about the size of my testicles.

Dr. Smith: Nor their wives, for that matter.

Scot: John, let’s wrap this up. I think we all know your bottom line. I think I’ve got your bottom line on testosterone treatments. If you’re experiencing these symptoms and you get a test and you’re in that low range or below, it could be a very good option to help you get some energy back, to help you with your sexual function, with few downsides, really.

Dr. Smith: Yeah. The downsides are minimal. If you’re one of those people who overproduces red blood cells or something like that, we keep an eye on it, but yeah, that is the bottom line. If you feel like it’s going to make a difference for you, there’s a lot of good that can come from it. And it doesn’t necessarily have to be a long-term thing. However, most of my patients that are on it are long term.

And I think if you do have questions, go talk to someone that knows what they’re talking about. I’m happy to sit down with people. Most of my new hypogonadism patients/low testosterone folks, I like to spend time going over the benefits, the risks, and everything that is involved is involved so that they have a clear picture of what options they have.

And I do have plenty of people who come in and say, “You know what, doc? I think I am going to try to lose 25 pounds and recheck my testosterone.” And then I have others who say, “You know what, doc? I just know myself and I’m not going to do that. And so I’m going to take the testosterone and try to do it that way.” I think there’s merit both ways. Absolutely.

Scot: John, thank you very much for having this conversation with us about testosterone. Hopefully, this will be helpful to a lot of guys. And bottom line, it sounds like perhaps guys who have talked to primary care physicians, haven’t gotten a lot of conversation, it sounds like if you do go to a men’s health expert, you’ve got a little bit more time to discuss through some of these issues and really come up with the right choice for each individual guy.

Dr. Smith: Absolutely. I’d be happy to see anybody in our men’s health department at The U. I think we do a great job at taking care of folks and making sure that we go over the options and making sure that we help you make the right decision for you.

Scot: Dr. Smith, thank you for being on the podcast and thank you for caring about men’s health.

Dr. Smith: Gents, thanks for having me. It’s always a pleasure.

Testosterone synthesis

testosterone synthesis

Testosterone Synthesis, Transport, and Metabolism

Testosterone, the major androgen in men, is necessary for fetal male sexual differen-tiation, pubertal development, the maintenance of adult secondary sex characteristics, and spermatogenesis, and functions in many other tissues, including muscle and bone, and in the immune system. The testes are the source of more than 95% of the circulating testosterone in men, although the adrenal cortex produces large amounts of the testoster-one precursor steroids dehydroepiandrosterone (DHEA) and androstenedione.

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Editors and Affiliations

  1. Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA Carrie J. Bagatell MD ( Clinical Assistant Professor ) & William J. Bremner MD, PhD ( The Robert G. Petersdorf Professor and Chairman ) ( Clinical Assistant Professor ) & ( The Robert G. Petersdorf Professor and Chairman )

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Winters, S.J., Clark, B.J. (2003). Testosterone Synthesis, Transport, and Metabolism. In: Bagatell, C.J., Bremner, W.J. (eds) Androgens in Health and Disease. Contemporary Endocrinology. Humana Press, Totowa, NJ. https://doi.org/10.1007/978-1-59259-388-0_1

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Is it normal for a man to have one testicle?

is it normal for a man to have one testicle?

What should my testicles look and feel like?

Most men’s testicles are about the same size, but it’s common for one to be slightly bigger than the other. It’s also common for one testicle to hang lower than the other.

The testicles should feel smooth, without any lumps or bumps, and firm but not hard. You may feel a soft tube at the back of each testicle, which is called the epididymis.

If you notice any changes or anything unusual about your testicles, you should see a GP.

What causes lumps and swelling in the testicles?

There are several causes of testicular lumps and swellings:

  • varicocele – caused by enlarged veins in the testicles (may look like a bag of worms)
  • hydrocele – a swelling caused by fluid around the testicle
  • epididymal cyst – a lump caused by a collection of fluid in the epididymis
  • testicular torsion – a sudden painful swelling that happens when a testicle becomes twisted (this is a medical emergency and requires surgery as soon as possible)
  • epididymitis – a chlamydia infection in the epididymis can cause inflammation, swelling and tenderness inside the scrotum (ball sack); a few men will notice that the whole of the scrotum is red and tender (this is called epididymo-orchitis)
  • testicular cancer – an uncommon cause of lumps

What are the signs of testicular cancer?

The early signs of testicular cancer are easy to spot. Look out for one or more of the following:

  • a hard lump on the front or side of a testicle
  • swelling or enlargement of a testicle
  • an increase in firmness of a testicle
  • pain or discomfort in a testicle or in the scrotum (the sac that holds the testicles)
  • an unusual difference between one testicle and the other

If you find a lump or swelling, or have any of the above signs, it’s important to get it checked out by a doctor.

Further information:

Page last reviewed: 6 April 2021
Next review due: 6 April 2024

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Where is testosterone produced

where is testosterone produced

Testosterone

Testosterone is a hormone that is responsible for many of the physical characteristics specific to adult males. It plays a key role in reproduction and the maintenance of bone and muscle strength.

Alternative names for testosterone

Testo (brand name for testosterone formulations); 4-androsten-17β-ol-3-one

What is testosterone?

Testosterone is produced by the gonads (by the Leydig cells in testes in men and by the ovaries in women), although small quantities are also produced by the adrenal glands in both sexes. It is an androgen, meaning that it stimulates the development of male characteristics.

Present in much greater levels in men than women, testosterone initiates the development of the male internal and external reproductive organs during foetal development and is essential for the production of sperm in adult life. This hormone also signals the body to make new blood cells, ensures that muscles and bones stay strong during and after puberty and enhances libido both in men and women. Testosterone is linked to many of the changes seen in boys during puberty (including an increase in height, body and pubic hair growth, enlargement of the penis, testes and prostate gland, and changes in sexual and aggressive behaviour). It also regulates the secretion of luteinising hormone and follicle stimulating hormone. To effect these changes, testosterone is often converted into another androgen called dihydrotestosterone.

In women, testosterone is produced by the ovaries and adrenal glands. The majority of testosterone produced in the ovary is converted to the principle female sex hormone, oestradiol.

How is testosterone controlled?

The regulation of testosterone production is tightly controlled to maintain normal levels in blood, although levels are usually highest in the morning and fall after that. The hypothalamus and the pituitary gland are important in controlling the amount of testosterone produced by the testes. In response to gonadotrophin-releasing hormone from the hypothalamus, the pituitary gland produces luteinising hormone which travels in the bloodstream to the gonads and stimulates the production and release of testosterone.

As blood levels of testosterone increase, this feeds back to suppress the production of gonadotrophin-releasing hormone from the hypothalamus which, in turn, suppresses production of luteinising hormone by the pituitary gland. Levels of testosterone begin to fall as a result, so negative feedback decreases and the hypothalamus resumes secretion of gonadotrophin-releasing hormone.

What happens if I have too much testosterone?

The effect excess testosterone has on the body depends on both age and sex. It is unlikely that adult men will develop a disorder in which they produce too much testosterone and it is often difficult to spot that an adult male has too much testosterone. More obviously, young children with too much testosterone may enter a false growth spurt and show signs of early puberty and young girls may experience abnormal changes to their genitalia. In both males and females, too much testosterone can lead to precocious puberty and result in infertility.

In women, high blood levels of testosterone may also be an indicator of polycystic ovary syndrome. Women with this condition may notice increased acne, body and facial hair (called hirsutism), balding at the front of the hairline, increased muscle bulk and a deepening voice.
There are also several conditions that cause the body to produce too much testosterone. These include androgen resistance, congenital adrenal hyperplasia and ovarian cancer.

The use of anabolic steroids (manufactured androgenic hormones) shuts down the release of luteinising hormone and follicle stimulating hormone secretion from the pituitary gland, which in turn decreases the amount of testosterone and sperm produced within the testes. In men, prolonged exposure to anabolic steroids results in infertility, a decreased sex drive, shrinking of the testes and breast development. Liver damage may result from its prolonged attempts to detoxify the anabolic steroids. Behavioural changes (such as increased irritability) may also be observed. Undesirable reactions also occur in women who take anabolic steroids regularly, as a high concentration of testosterone, either natural or manufactured, can cause masculinisation (virilisation) of women.

What happens if I have too little testosterone?

If testosterone deficiency occurs during fetal development, then male characteristics may not completely develop. If testosterone deficiency occurs during puberty, a boy’s growth may slow and no growth spurt will be seen. The child may have reduced development of pubic hair, growth of the penis and testes, and deepening of the voice. Around the time of puberty, boys with too little testosterone may also have less than normal strength and endurance, and their arms and legs may continue to grow out of proportion with the rest of their body.

In adult men, low testosterone may lead to a reduction in muscle bulk, loss of body hair and a wrinkled ‘parchment-like’ appearance of the skin. Testosterone levels in men decline naturally as they age. In the media, this is sometimes referred to as the male menopause (andropause).
Low testosterone levels can cause mood disturbances, increased body fat, loss of muscle tone, inadequate erections and poor sexual performance, osteoporosis, difficulty with concentration, memory loss and sleep difficulties. Current research suggests that this effect occurs in only a minority (about 2%) of ageing men. However, there is a lot of research currently in progress to find out more about the effects of testosterone in older men and also whether the use of testosterone replacement therapy would have any benefits.

Testosterone meaning in hindi

testosterone, meaning of testosterone, testosterone in hindi, testosterone translation,testosterone definition, pronunciation of testosterone, testosterone rhymes

testosterone – Meaning in Hindi

Testosterone is the primary male sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. It is associated with increased sex drive, the inclination to impress partners and other courting behaviors. In addition, testosterone in both sexes is involved in health and well-being, where it has a significant effect on overall mood, cognition, social and sexual behaviour, metabolism and energy output, bilat the cardiovascular system, and in the prevention of osteoporosis. Insufficient levels of testosterone in men may lead to abnormalities including frailty, accumulation of adipose fat tissue within the body, anxiety and depression, sexual performance issues, and bone loss. टेस्टोस्टेरॉन एंड्रोजन समूह का एक स्टीरॉएड हार्मोन है। स्तनपाइयों में टेस्टॉस्टेरॉन प्राथमिक रूप से नरों में अंडकोष से व मादाओं में अंडाशय से स्रावित होता है। हालांकि कुछ मात्रा अधिवृक्क ग्रंथि से भी स्रवित होती है। यह प्रधान नर-सेक्स हार्मोन एवं एक एनाबोलिक स्टीरॉएड होता है। टेस्टोस्टेरॉन पुरुष यौन लक्ष्णों के विकास को बढ़ाता है और इसका संबंध यौन क्रियाकलापों, रक्त संचरण और मांसपेशियों के परिमाण के साथ साथ एकाग्रता, मूड और स्मृति से भी होता है। जब कोई पुरुष चिड़चिड़ा या गुस्सैल हो जाता है तो लोग इसे उसके काम या आयु का प्रभाव मानते हैं, पर यह टेस्टोस्टेरॉन की कमी से भी होता है। एक परीक्षण के अनुसार, इससे प्रभावित अधिकतर लोग ३५ साल से कम आयु के थे और कुछ की तो एक दो साल पहले ही शादी हुई थी। इसके अनुसार टेस्टोस्टेरॉन का स्तर निर्णय लेने में महत्त्वपूर्ण भूमिका निभाता है और जिन रोगियों मेंउनकी जानकारी के बगैर इसका स्तर बढ़ाया गया, उनका सामाजिक व्यवहार अन्य की तुलना में समाज के प्रति अधिक सकारात्मक हो गया। जिन रोगियों का मानना था कि टेस्टोस्टेरॉन अधिकता से आक्रामक व्यवहार उत्पन्न होता है अथवा जिन्होंने जानकारी में मात्रा ली, उनका प्रदर्शन अपेक्षाकृत कम ठीक रहा। पुरुषत्व के हार्मोन टेस्टोस्टेरॉन मांसपेशियां सुगठित बनाने में भी सहायक होता है। चिकित्सकों के अनुसार टेस्टोस्टेरॉन की अधिक मात्र के दुष्प्रभाव भी हो सकते हैं। Also see ” Testosterone ” on Wikipedia

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What is testosterone meaning in Hindi?

The word or phrase testosterone refers to a potent androgenic hormone produced chiefly by the testes; responsible for the development of male secondary sex characteristics. See testosterone meaning in Hindi, testosterone definition, translation and meaning of testosterone in Hindi. Learn and practice the pronunciation of testosterone. Find the answer of what is the meaning of testosterone in Hindi. देखें testosterone का हिन्दी मतलब, testosterone का मीनिंग, testosterone का हिन्दी अर्थ, testosterone का हिन्दी अनुवाद।

Tags for the entry “testosterone”

What is testosterone meaning in Hindi, testosterone translation in Hindi, testosterone definition, pronunciations and examples of testosterone in Hindi. testosterone का हिन्दी मीनिंग, testosterone का हिन्दी अर्थ, testosterone का हिन्दी अनुवाद

What are normal testosterone levels for a 40 year old man?

How to think about testosterone levels in men over 40

Written on January 30, 2023 by Sendra Yang, PharmD, MBA. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

As you age, your hair turns gray, and you may notice more wrinkles on your skin. Other things also change as you age, including your hormones. In men, testosterone is a hormone that declines with age [1]. If you are over 40 years old, it’s important to understand more about testosterone and how to think about your levels.

What is testosterone?

Testosterone is a steroid hormone produced primarily by the testicles in men [1]. It plays a crucial role in developing and maintaining male physiological characteristics such as muscle mass, bone density, and body hair [1,2]. Testosterone also helps regulate mood, sex drive, and sperm production [1,2]. As men age, their testosterone levels decline naturally [1]. The testosterone decline can start as early as age 30 and continue through the remainder of a man’s life [2].

Common symptoms of low testosterone

According to the American Urological Association (AUA), a testosterone level below 300 ng/dL should be diagnosed as a low level of testosterone [3]. Low testosterone in men, sometimes referred to as male hypogonadism or low T, can cause various symptoms and lead to unwanted health concerns. Common symptoms of low testosterone in men can include [2,3]:

  • Fatigue and low energy levels
  • Low sex drive and erectile dysfunction
  • Loss of muscle mass and strength
  • Increased body fat and decreased bone density
  • Reduced body hair and changes in skin texture
  • Depression, irritability, and inability to concentrate

Some of these symptoms can also be caused by other health conditions. Not all men with low testosterone will experience all of these symptoms [2,3].

How is low testosterone tested?

If you are concerned about your testosterone levels, you should consider getting tested. The tests available measures the different types of testosterones in your blood or saliva. The most common testosterone tests are [4]:

  • Total testosterone: This test measures overall free testosterone levels in your blood.
  • Free testosterone: This test measures the most active amount of testosterone that is not bound to proteins in the blood.

Everlywell provides an at-home lab test that will measure and help you understand your testosterone level. With Everlywell, your test result will provide detailed information on whether your free testosterone level is normal, low, or high. When you receive your results, you’ll also receive lifestyle tips for maintaining healthy testosterone levels and your overall wellness.

Next steps after receiving your at-home lab test result

If you’re experiencing signs and symptoms of abnormal testosterone levels, sharing your test results with your healthcare provider for further guidance is important. Your healthcare provider may need to repeat the test or order additional tests to confirm or rule out other causes of your symptoms [3]. It’s a great idea to share your results with your healthcare provider. Additionally, your results from the testosterone level at-home lab test with Everlywell will include information on evidence-based lifestyle changes that support healthy testosterone levels.

Telehealth for low testosterone

If you’re concerned about your testosterone levels, telehealth with a healthcare provider to discuss testosterone testing and treatment can offer several benefits:

  • Convenience: Virtual visits from the comfort of your home without needing to travel to a clinic or doctor’s office
  • Accessibility: Virtual visits offer easier access for men in remote or underserved areas
  • Flexibility: Virtual visits can be scheduled outside of traditional office hours, making it easier to fit appointments into a busy schedule

During the virtual visit, you will have the opportunity to discuss your symptoms, medical history, lab tests, and other medications you are currently taking. The healthcare provider may recommend further testing or treatment options based on this information.

At Everlywell, we have a Men’s Health Virtual Visit telehealth option where you can book an appointment with a health provider to discuss low testosterone who can evaluate your symptoms and offer guidance on the next steps.

Are there treatment options for low testosterone?

If you are diagnosed with low testosterone, your healthcare provider can recommend several options for treatment, including [3,5]:

  • Testosterone replacement therapy (TRT): TRT is a standard treatment for low testosterone and can help alleviate symptoms such as low sex drive, muscle loss, and fatigue. The therapy involves taking a synthetic form of testosterone, usually a gel, patch, injection, or pellet, to help bring your testosterone levels back to normal. Testosterone replacement therapy is not without its risks, and benefits are carefully weighed against the risks with your healthcare provider. Common TRT side effects are breast enlargement and an increased risk of prostate cancer. TRT is not always the best option for all men.
  • Clomiphene citrate: This oral medication helps boost testosterone levels by stimulating the production of luteinizing hormone, which causes the testes to produce more testosterone.
  • Human Chorionic Gonadotropin (hCG): This hormone can stimulate the testes to produce more testosterone and is usually administered via injection.
  • Lifestyle changes: Changing your diet and exercise routine can help improve your overall health and boost your testosterone levels. Regular exercise and a healthy diet rich in nutrients can help increase muscle mass, reduce body fat, and improve overall health.

It is essential to communicate with your healthcare provider and monitor testosterone levels regularly to ensure that the treatment works and adjust the dosage as necessary.

To get started, you can consider an at-home lab test (such as the Testosterone Test) and/or a Men’s Health Virtual Visit with Everlywell.

Related content

  1. Nassar GN, Leslie SW. Physiology, testosterone – STATPEARLS – NCBI BOOKSHELF. URL. Accessed January 26, 2023.
  2. Jia H, Sullivan CT, McCoy SC, Yarrow JF, Morrow M, Borst SE. Review of health risks of low testosterone and testosterone administration. World J Clin Cases. 2015;3(4):338-344. doi:10.12998/wjcc.v3.i4.338. URL.
  3. Mulhall JP, Trost LW, Brannigan RE, et al. Evaluation and management of testosterone deficiency: AUA guideline. J Urol. 2018;200(2):423-432. doi: 10.1016/j.juro.2018.03.115. URL.
  4. Testosterone levels test. MedlinePlus. URL. Accessed January 25, 2023.
  5. Kumagai H, Zempo-Miyaki A, Yoshikawa T, Tsujimoto T, Tanaka K, Maeda S. Increased physical activity has a greater effect than reduced energy intake on lifestyle modification-induced increases in testosterone. J Clin Biochem Nutr. 2016;58(1):84-89. doi:10.3164/jcbn.15-48. URL.

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What is the average free testosterone level?

what is the average free testosterone level?

Testosterone, Free and Total, Males (Adult), Immunoassay

CPT Code: 84270, 84403, 82040
Order Code: C942
Includes: Total Testosterone, % Free Testosterone (calculated), Free Testosterone (calculated), Sex Hormone Binding Globulin (SHBG) and Albumin)
ABN Requirement: No
Synonyms: % Free; Free Testosterone
Specimen: Serum
Volume: 2.0 mL
Minimum Volume: 1.0 mL
Container: Gel-barrier tube (SST, Tiger Top)

  1. Collect and label sample according to standard protocols.
  2. Gently invert tube 5 times immediately after draw. DO NOT SHAKE.
  3. Allow blood to clot 30 minutes.
  4. Centrifuge for 10 minutes.

Patient Preparation: Due to changes in testosterone levels throughout the day, two morning (8:00-10:00 a.m.) specimens obtained on different days are recommended by The Endocrine Society for screening.

Special Instructions: Samples should not be taken from patients receiving therapy with high biotin doses (>5 mg/day), until at least 8 hours following the last biotin administration.

Transport: Store serum at 2°C to 8°C after collection and ship the same day per packaging instructions included with the provided shipping box.

Ambient (15-25°C): Not Acceptable
Refrigerated (2-8°C): 5 days
Frozen (-20°C): 1 month

Causes for Rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits; gross hemolysis; gross lipemia

Methodology: Immunoassay, Colorimetric Assay, Calculation

Turn Around Time: 1 to 3 days

Male ≥18 years old
Free Testosterone 4.5-25.0 ng/dL
% Free Testosterone 1.1-3.0%
Age/Stage
ng/dL
Total Testosterone 18-49 years 249-836
Total Testosterone ≥50 years 193-740

Clinical Significance: Total testosterone circulates primarily as protein-bound (approximately 60% bound to sex hormone binding globulin (SHBG) and 50% to albumin). Only 2-3% exists in free, biologically-active form. Testosterone is weakly bound to albumin and can be reversed easily, therefore albumin-bound and free testosterone are considered to be bioavailable testosterone. The highest testosterone level peaks at 30 to 40 years of age, in adult men. The levels start to decline steadily after the fourth or fifth decade of adult male life. Decreased levels of testosterone and/or free testosterone indicate partial or complete hypogonadism. It is important to determine if low levels of testosterone are due to aging or a pathological disorder. In adult men, testicular or androgen abuse might be suspected if testosterone levels exceed the upper limit of the normal range by more than 50%.

The free testosterone test may be used to evaluate infertility, erectile dysfunction, or osteoporosis in men, and to evaluate hirsutism, polycystic ovarian disease, and virilization in women. The test may also be used to monitor the efficacy of testosterone-lowering therapies in prostate cancer.

The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.