Is TRT Safe? What the Research Actually Says About Testosterone Therapy Risks

For about a decade, the honest answer to "is testosterone therapy safe for my heart" was that nobody knew. A boxed warning sat on every product, the research pointed in several directions at once, and men were left to weigh a vague risk against a real set of symptoms.

That changed. Here is what the evidence actually shows now, what the FDA did about it, and which risks are genuinely worth your attention.

The heart question, and what TRAVERSE found

TRAVERSE was the trial designed to settle it. Published in the New England Journal of Medicine, it randomized 5,204 men aged 45 to 80 to either a daily transdermal testosterone gel or placebo. Every participant had documented hypogonadism, meaning a serum testosterone below 300 ng/dL, plus either existing cardiovascular disease or high cardiovascular risk. In other words, the trial deliberately recruited the men most likely to have a cardiac event.

Mean treatment duration was 21.7 months, with an average follow-up of 33 months.

The primary endpoint combined cardiovascular death, nonfatal heart attack, and nonfatal stroke. It occurred in 7.0% of the testosterone group and 7.3% of the placebo group, a hazard ratio of 0.96. The trial met its noninferiority threshold. Testosterone therapy did not increase major adverse cardiovascular events in this population.

What the FDA did with that

On February 28, 2025, the FDA issued class-wide labeling changes for testosterone products, based on TRAVERSE and on a set of postmarket ambulatory blood pressure monitoring studies. Three things happened:

1. The TRAVERSE findings were added to all testosterone product labels
2. The Boxed Warning language about increased risk of adverse cardiovascular outcomes was removed
3. New or strengthened warnings about increased blood pressure were added, because the monitoring studies confirmed a blood pressure increase across the entire class

The FDA also retained the Limitation of Use language for age-related hypogonadism. The products are labeled for hypogonadism with a recognized medical cause, not for ordinary age-related decline.

The cardiovascular boxed warning came off. A blood pressure warning went on. Both of those are the system working correctly, and both matter to how your care should be run.

The risks that are real

Removing one warning does not make a medication risk-free. TRAVERSE itself found three conditions occurring significantly more often in the testosterone group:

• Atrial fibrillation, 3.5% versus 2.4% on placebo
• Acute kidney injury, 2.3% versus 1.5%
• Pulmonary embolism, 0.9% versus 0.5%

Add to that the class-wide blood pressure effect the FDA flagged, and one more the AUA singles out: polycythemia, an overproduction of red blood cells that thickens the blood. The AUA recommends measuring hemoglobin and hematocrit before therapy begins and counseling patients about that risk specifically.

Fertility is a separate consideration. Testosterone therapy suppresses sperm production. Cleveland Clinic notes that clomiphene citrate is an option for men who want to preserve fertility, which is a conversation to have before starting, not after.

The caveat that matters most

The TRAVERSE investigators attached a warning to their own good news, and it deserves more attention than it got.

They emphasized that the findings apply specifically to middle-aged and older men with symptoms of hypogonadism and confirmed low testosterone levels. They cautioned that the results should not be used to justify broad testosterone prescribing to aging men without hypogonadism, and named low T centers operating without proper monitoring as the concern.

Read that carefully and the picture is clear. The safety data applies to men who genuinely have the condition and who are being monitored. It does not extend to a man who filled out a web form, never had a properly timed lab draw, and has not had his levels rechecked since.

What responsible monitoring looks like

The AUA sets the standard, and it is not complicated:

1. Diagnosis only when low total testosterone is combined with symptoms or signs, never on symptoms alone
2. Two total testosterone measurements on separate occasions, both drawn in the early morning
3. Hemoglobin and hematocrit measured before therapy starts
4. Testosterone levels rechecked every 6 to 12 months while on therapy
5. Dosing adjusted toward the middle of the normal reference range, not pushed as high as possible

That is the checklist. If a clinic is not doing all five, the reassuring TRAVERSE data was not collected on anything resembling the care you are receiving.

At CarePrime Men, Christopher Brown, FNP-C manages each protocol personally from the first lab draw forward, so the monitoring schedule does not fall through the gap between rotating clinicians. How It Works walks through the sequence, and the Treatments page covers the protocols.

Weighing it honestly

Testosterone therapy is a real medication with real effects in both directions. The heart question has a much better answer than it did five years ago. Blood pressure, hematocrit, and fertility are genuine considerations that a good provider raises with you up front rather than after you have started.

What makes it responsible is not the molecule. It is whether anyone is watching.

Where to start

If you have not established whether you actually have low testosterone, that is the first question, and our guide to low testosterone symptoms covers what proper testing involves. The free ADAM symptom check takes two minutes. If the cost side is what is holding you up, our breakdown of what TRT costs in Georgia covers that.

CarePrime Men is licensed in Georgia and works with men across Brunswick, St. Simons Island, Jekyll Island, Darien, and the wider Golden Isles by telemedicine. Pricing is published on the Pricing page, common questions on the FAQs page, and a free consultation starts through the contact form.

Sources

• Lincoff et al., Cardiovascular Safety of Testosterone-Replacement Therapy, New England Journal of Medicine (TRAVERSE)
• Cleveland Clinic, TRAVERSE Study Supports Cardiovascular Safety of Testosterone Therapy When Used as Indicated
• U.S. Food and Drug Administration, Class-Wide Labeling Changes for Testosterone Products (February 2025)
• American Urological Association, Evaluation and Management of Testosterone Deficiency Guideline
• Cleveland Clinic, Low Testosterone (Male Hypogonadism)

This article is general health education, not medical advice. Testosterone therapy carries risks that depend on your own health history, and the decision requires lab work and a clinical evaluation. Talk with a licensed provider about your situation.