Testosterone replacement therapy is often prescribed to men whose bodies do not produce adequate amounts of testosterone on their own, a condition called hypogonadism. This can happen when there is a problem with the part of the brain that triggers testosterone production or with the testes themselves (the glands that make this hormone).
The therapy may also be prescribed to older men whose testosterone levels have declined during the natural course of aging. These men may find that their sex drive has diminished and that they feel fatigued and weak. Replenishing their testosterone levels may improve these symptoms.
Some of the more common side effects of testosterone therapy include the following:
- Itching and irritation. This may occur wherever a testosterone patch or gel is applied. It tends to be less common for gel users.
- Increase in body hair
- Hot flashes
- Changes in cholesterol levels
- Changes in red blood cell counts
- Weight gain – due to salt and water retention (not fat accumulation)
- Gynecomastia. Some men develop more breast tissue or feel tenderness in this area, but return to normal if testosterone therapy is stopped.
- Acne and/or oily skin. This side effect usually ends when a man stops taking testosterone.
Testosterone therapy also lowers sperm counts, so it is generally not recommended for men with fertility concerns.
Although no conclusive evidence exists, testosterone therapy is suspected to spur the growth of prostate cells and prostate cancer cells. Men with prostate cancer are usually advised against testosterone therapy. Men should be screened for prostate cancer before starting treatment.
Testosterone can also have adverse effects for men with breast cancer.
Testosterone therapy has been linked to sleep apnea, a disorder that causes people to stop breathing for repeated short intervals during the night. These episodes can deprive the brain of oxygen.
To avoid transferring testosterone to another person, men using the gel should wash their hands immediately after applying it. Before sex, they should shower or cover the application site so the gel doesn’t transfer to the partner. For example, since men usually apply the gel to the shoulders, upper arms, or abdomen, some men wear a shirt during sex.
Men who think they might benefit from testosterone therapy should see their doctor. Symptoms of low testosterone can be caused by many different medical conditions, and it’s important to have a complete checkup.
Some men are reluctant to discuss their symptoms with a doctor, especially if they are having trouble performing sexually. In some cases, men buy over-the-counter testosterone products online or in stores. But this practice is risky, as some products contain other ingredients that can interact with drugs a man is already taking. It is always safest to see a healthcare provider.
In spite of the difficulty of discussing sexual symptoms with a doctor or a sex therapist, men who overcome their embarrassment find that receiving proper professional information and sexual counseling may contribute to successful medical treatment by testosterone.