Important Safety Information: testosterone

Testosterone products are FDA-approved for men who have low testosterone together with an associated medical condition. The labels name two groups: primary hypogonadism, where the testicles fail (for example after torsion, orchitis or removal), and hypogonadotropic hypogonadism, where the pituitary or hypothalamus does not send the signal (for example from a tumor, trauma or radiation).

The current labels also state that the safety and efficacy of testosterone in men with "age-related hypogonadism" (also referred to as "late-onset hypogonadism") have not been established. In June 2026 FDA requested that manufacturers remove this limitation and revise the prostate information. FDA requested these changes; the labels we checked on November 1, 2026 still carry the limitation.

Testosterone is FDA-approved for men with low testosterone caused by certain medical conditions. Its safety and effectiveness for low testosterone due to aging alone have not been established. Testosterone can raise blood pressure and red blood cell count, reduce sperm production and fertility, and requires monitoring of the prostate and blood levels. Your provider will review the benefits and risks and monitor you with regular labs.

Testosterone is not for everyone. The labels list these contraindications:

• men with breast cancer, or with known or suspected prostate cancer;
• women who are pregnant, and for products applied to the skin, women who may become pregnant or are breastfeeding, because testosterone can harm an unborn baby;
• known allergy to the product;
• serious heart, liver or kidney disease (listed on the testosterone cypionate label).

These are the serious risks the labels describe. Your provider weighs them against your health history before any decision.

• Blood pressure: testosterone can increase blood pressure, which can increase cardiovascular risk over time. The labels say to measure blood pressure periodically and do not recommend testosterone for people with uncontrolled high blood pressure.
• Red blood cell count: testosterone can raise hematocrit and hemoglobin (polycythemia). A higher red blood cell mass may increase the risk of blood clots. Treatment may need to stop until levels come down.
• Blood clots: blood clots in the legs (deep vein thrombosis) and lungs (pulmonary embolism) have been reported in people using testosterone products.
• Heart attack and stroke: the testosterone cypionate label states that studies have been inconclusive about the risk of major cardiovascular events, and that some studies, but not all, reported an increased risk. Patients should be told about this possible risk when deciding whether to start or continue. Other testosterone labels report the TRAVERSE trial, in which major heart events were similar with testosterone gel and placebo, with a numerically higher rate of blood clots.
• Prostate: men with an enlarged prostate (BPH) can have worsening urinary symptoms, including sudden blockage. Men on testosterone may be at increased risk for prostate cancer, so the labels call for evaluation before and during treatment.
• Fertility: prolonged use or high doses can lower sperm counts (oligospermia), and some labels warn that testosterone may lead to no sperm in the semen (azoospermia).
• Swelling: fluid retention (edema), with or without heart failure, can be a serious complication in people with existing heart, kidney or liver disease.
• Other effects named in the labels: breast enlargement in men (gynecomastia), sleep apnea in people with risk factors, high calcium in people who are immobilized, and liver tumors with prolonged high doses of certain oral androgens. One testosterone enanthate label reports depression and suicidal thoughts and behavior, including completed suicide, during clinical trials.

Testosterone is a Schedule III controlled substance because it can be misused. Abuse and dependence have been reported, mostly at doses above those prescribed. Take it only as your provider directs.

The labels describe serious problems in people who misuse testosterone, often with other androgens, including heart attack, heart failure, stroke, liver damage and serious psychiatric effects such as depression, mania, paranoia and aggression. Stopping high doses suddenly can cause withdrawal symptoms such as depressed mood, fatigue, irritability, insomnia and decreased libido. The labels state that dependence has not been documented in people using approved doses for approved uses.

The labels list these among the reported side effects: acne, oily skin, increased body hair, male-pattern hair loss, breast enlargement, more frequent or longer erections, nausea, headache, anxiety, depression, changes in libido, and pain or swelling where the medicine is applied or injected. Tell your provider about any side effect that bothers you or does not go away.

The labels call for periodic checks of hematocrit and hemoglobin, blood pressure, testosterone levels and prostate health (including PSA), and some labels add cholesterol. Your provider decides how often you have follow-up labs and reviews based on your results and history.

Tell your provider about all medicines you take. Testosterone can increase the effect of blood thinners taken by mouth, and it can lower blood sugar in people with diabetes, so insulin needs may change.

Call 911 or get emergency care for chest pain, sudden shortness of breath, or symptoms of a reaction during or after an injection such as throat tightening, an urge to cough or fainting. Contact your provider promptly for pain, swelling, warmth or redness in one leg; ankle swelling; nausea, vomiting or yellowing of the skin; erections that are too frequent or last too long; trouble urinating; or if a child or a woman may have been exposed to a product applied to your skin.

You can report side effects to FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Testosterone is a Schedule III controlled substance. Depending on your state, and on federal telemedicine rules that are currently set to change after December 31, 2026, an in-person exam may be required before or during treatment. The current federal telemedicine flexibilities run through December 31, 2026 under the fourth temporary extension (90 FR 61301).

Prescription treatment requires an evaluation by a licensed healthcare provider, who decides whether treatment is appropriate for you. Not everyone qualifies. Completing an assessment, booking a visit, or paying a fee does not guarantee a prescription.