Testosterone supplements are not automatically safe. Prescription testosterone replacement therapy may help people with confirmed testosterone deficiency, but it can cause serious side effects and requires medical monitoring. Over-the-counter "testosterone boosters" are less predictable. Most have limited evidence, and some may contain excessive doses, hidden steroids or other undeclared ingredients.
In February 2025, the FDA required blood pressure warnings across testosterone products. The TRAVERSE trial, which included 5,246 men, did not find a higher rate of major cardiovascular events with testosterone gel than with placebo, but that result does not make testosterone risk-free.
The first step is to separate prescribed testosterone from products sold as "natural testosterone support."
Testosterone Supplements: Safety at a Glance
| Product type | What it is | Safety verdict |
|---|---|---|
| Prescription testosterone replacement therapy | Testosterone gel, injections, patches, oral medicines and other FDA-regulated treatments | May be suitable for people with diagnosed hypogonadism when prescribed and monitored |
| Over-the-counter testosterone booster | Vitamins, minerals, herbs or proprietary blends | Not proven to reliably raise testosterone; safety and product quality vary |
| Bodybuilding products, anabolic steroids or SARMs | Unapproved substances marketed for muscle gain or performance | Avoid without specialist medical supervision because serious, potentially life-threatening harms are possible |
The FDA does not approve dietary supplements for safety or effectiveness before they are sold. It has also found bodybuilding products marketed as supplements that contained hidden steroids or steroid-like ingredients.
Is Prescription Testosterone Replacement Therapy Safe?
Prescription testosterone therapy can be safe for some patients when low testosterone is confirmed and treatment is supervised by a healthcare professional. It is not a general treatment for low energy, muscle gain or aging.
The Endocrine Society recommends diagnosing hypogonadism only when a person has compatible symptoms and consistently low testosterone levels. Treatment should also address the likely cause of the deficiency. Symptoms alone are not enough.
The TRAVERSE trial included 5,246 men aged 45 to 80 who had symptoms, repeatedly low testosterone and existing or elevated cardiovascular risk. Major cardiovascular events occurred in 7.0% of the testosterone group and 7.3% of the placebo group. The trial did not show an increased rate of major cardiovascular events, but it does not prove that testosterone is safe for every person or every type of use.
Testosterone can raise blood pressure. In February 2025, the FDA required class-wide label changes after blood pressure monitoring studies found increases across testosterone products. Blood pressure should be checked during treatment, especially in people with hypertension or cardiovascular disease.
The FDA requested further label updates on June 18, 2026, in response to newer evidence about cardiovascular and prostate risks. Those changes do not make unsupervised testosterone use safe. Long-term follow-up remains part of treatment.
What Are the Main Risks of Prescription Testosterone?
The main risks include changes to blood pressure, blood cell levels, fertility, sleep, prostate health and the cardiovascular system.
Possible adverse effects include:
- High red blood cell levels, also called erythrocytosis or polycythemia
- Reduced sperm production and infertility
- Increased blood pressure
- Acne and oily skin
- Breast enlargement or tenderness
- Fluid retention and swelling
- Worsening or triggering of sleep apnea
- Worsening urinary symptoms in some people with prostate enlargement
- Blood clots, including deep vein thrombosis or pulmonary embolism
- Transfer of topical testosterone to another person through skin contact
Testosterone therapy can suppress the body's natural hormone production. For that reason, testosterone replacement is generally unsuitable for someone who is actively trying to conceive unless a fertility specialist recommends another treatment plan.
Testosterone and Prostate Health
Current evidence has not generally shown that medically supervised testosterone therapy increases prostate cancer risk. Long-term uncertainty remains, however, because prostate cancer can develop slowly.
Clinicians should assess prostate risk before treatment and monitor patients during therapy. People with prostate symptoms or an abnormal PSA result may need further evaluation before starting testosterone.
Who Should Not Start Testosterone Without Medical Evaluation?
People with fertility plans, untreated sleep apnea, high blood pressure, blood count problems, cardiovascular disease or possible prostate cancer should not start testosterone without medical evaluation.
A healthcare professional should assess people who have:
- A plan to have children soon
- A high hematocrit or red blood cell count
- Untreated severe obstructive sleep apnea
- Uncontrolled high blood pressure
- Significant urinary symptoms
- Uncontrolled heart failure
- A recent heart attack or stroke
- A history of blood clots or thrombophilia
- Possible prostate or breast cancer
- An abnormal PSA level or prostate examination
These conditions do not all make testosterone permanently impossible. They may make treatment unsuitable for now, require further testing or call for specialist supervision.
Product labels and clinical guidance change over time. Treatment decisions should be based on current prescription information and the individual's medical history.
Are Over-the-Counter Testosterone Boosters Safe?
Over-the-counter testosterone boosters should not be assumed to be safe or effective.
These products may contain zinc, magnesium, vitamin D, fenugreek, ashwagandha, tongkat ali, tribulus or D-aspartic acid. Some ingredients may help people with a specific deficiency. That is different from reliably treating testosterone deficiency.
A systematic review of 52 studies covering 27 proposed testosterone boosters found that most did not increase total testosterone. Earlier research on 50 commercial testosterone supplements found that many products had no supporting evidence. Some contained vitamin or mineral amounts above established upper intake limits.
Possible risks include:
- Undeclared anabolic steroids or steroid-like drugs
- Excessive zinc, vitamin B6, niacin or other nutrients
- Liver injury
- Drug interactions
- Contamination or inconsistent dosing
- False reassurance that delays diagnosis of a medical condition
"Natural," "herbal" and "FDA registered" do not mean that a product is safe, effective or FDA-approved.
How Do You Check Whether Low Testosterone Needs Treatment?
Start with a medical assessment, repeat morning testosterone testing when appropriate and investigate the cause before considering treatment.
- Discuss symptoms with a healthcare professional. Fatigue, low mood, erectile difficulties and reduced muscle mass can have many causes.
- Confirm the result with appropriate testing. Diagnosis generally requires symptoms plus consistently low testosterone, usually measured with morning blood tests.
- Investigate the cause. Possible causes include testicular disease, pituitary problems, obesity, sleep disorders, medication effects and other medical conditions.
- Review fertility plans, blood pressure, sleep apnea risk, prostate health and blood counts.
- Use only a prescribed product and attend follow-up monitoring.
Do not use bodybuilding steroids, SARMs or internet-sourced testosterone as substitutes for prescribed treatment. The FDA associates unapproved bodybuilding products with liver injury, kidney damage, heart attack, stroke, blood clots, infertility and testicular shrinkage.
Bottom Line
Prescription testosterone may be suitable for a person with confirmed low testosterone who receives appropriate monitoring. Over-the-counter boosters have weaker evidence and less predictable quality.
If you are considering a testosterone product, arrange testing and medical advice before taking it. If you already use one and develop chest pain, shortness of breath, one-sided leg swelling, severe headache, jaundice or another serious symptom, seek urgent medical care.