Evidence explainerMen's Hormones & TRT

Testosterone and Heart Risk: What the TRAVERSE Trial Found and What the FDA Changed

For a decade testosterone labels warned about heart attacks and strokes. TRAVERSE, the FDA-required safety trial, found no increase in major heart events, and in February 2025 the FDA removed that boxed-warning language and added a blood-pressure warning. Atrial fibrillation, kidney injury and lung clots were more common on testosterone.

By Kymata Labs EditorialPublished October 11, 2026Last verified October 11, 2026

Medical review pending. Written by our editorial team from the studies and documents cited below; a credentialed clinician has not reviewed it yet. Educational only, not medical advice.

Key takeaways

  • TRAVERSE randomized 5,246 men aged 45 to 80 with heart disease or high heart risk; major heart events occurred in 7.0% on testosterone gel and 7.3% on placebo, meeting the test for non-inferiority [1].
  • Atrial fibrillation, acute kidney injury and pulmonary embolism were more common on testosterone [1]; the label lists atrial fibrillation at 3.5% vs 2.4% [2].
  • On Feb 28, 2025 the FDA removed boxed-warning language about cardiovascular risk from all testosterone products, added the TRAVERSE results, and required a blood-pressure warning [3].
  • In June 2026 the FDA asked makers to remove the statement that safety and efficacy in age-related low testosterone are not established [4].
  • The AUA guideline still asks clinicians to tell patients it cannot be stated definitively whether testosterone raises or lowers cardiovascular risk [5].

Why the heart question came up

In 2010 a trial of testosterone gel in 209 men aged 65 and older with limited mobility was stopped early: 23 men on testosterone had cardiovascular-related adverse events, against 5 on placebo. The authors cautioned that the trial was small and its population unusual [6].

Two observational studies followed. A 2013 study of veterans with low testosterone who had coronary angiography reported more deaths, heart attacks and strokes among men who started testosterone [7], and a 2014 study found a higher rate of non-fatal heart attack in the 90 days after a first testosterone prescription, most clearly in men 65 and older [8].

The FDA issued a safety communication in January 2014, convened an advisory committee that September, required labeling changes in March 2015, and recommended an industry-wide trial: TRAVERSE [3].

How TRAVERSE was run

TRAVERSE was a randomized, double-blind, placebo-controlled trial. It enrolled 5,246 men aged 45 to 80 who had symptoms of low testosterone, two fasting testosterone levels below 300 ng/dL, and existing heart disease or a high risk of it. Men used daily 1.62% testosterone gel, with the dose adjusted to keep levels between 350 and 750 ng/dL, or a placebo gel [1].

The main safety endpoint was the first of cardiovascular death, non-fatal heart attack or non-fatal stroke. Mean treatment lasted 21.7 months and mean follow-up 33 months. The trial was funded by AbbVie and others [1].

What it found

The headline result was reassuring on heart attacks and strokes, but several other events were more common on testosterone.

  • Major heart events: 182 men (7.0%) on testosterone vs 190 (7.3%) on placebo, a hazard ratio of 0.96 (95% CI 0.78 to 1.17), which met the trial's non-inferiority test [1].
  • Each part of the composite (cardiovascular death, heart attack, stroke) appeared similar between groups [1].
  • Higher on testosterone: atrial fibrillation (3.5% vs 2.4%), acute kidney injury (2.3% vs 1.5%), non-fatal arrhythmias needing treatment (5.2% vs 3.3%) and bone fractures (3.5% vs 2.5%) [2].
  • Clots: venous thromboembolism 1.7% vs 1.2%, including pulmonary embolism 0.9% vs 0.5% [2].
  • Blood pressure: systolic pressure rose 1.0 mm Hg on testosterone and fell 0.5 mm Hg on placebo by 36 months, a 1.5 mm Hg difference [2].

What TRAVERSE does not settle

TRAVERSE tested one gel, not injections, which raise hematocrit more than gels [5]. Mean treatment (21.7 months) was well short of mean follow-up (33 months), so many men were off their assigned treatment for part of the trial, although results were similar in analyses that censored events after stopping [1].

Earlier pooled evidence pointed the same way with less precision. A 2022 meta-analysis of individual data from 17 randomized trials (3,431 men, mean treatment 9.5 months) found cardiovascular events in 7.5% on testosterone and 7.2% on placebo, a non-significant difference [9].

The AUA's 2024 guideline page still recommends counseling that it cannot be stated definitively whether testosterone therapy increases or decreases the risk of cardiovascular events [5].

What the FDA changed on the label

The label changed in two steps after TRAVERSE.

  • February 28, 2025: the FDA told makers of all testosterone products to add the TRAVERSE results, remove boxed-warning language about increased risk of adverse cardiovascular outcomes, keep the limitation-of-use language for age-related hypogonadism at that time, and add a warning about increased blood pressure. Blood-pressure monitoring studies had confirmed a class-wide rise [3].
  • June 2026: after further review, the FDA requested removal of the limitation of use stating that safety and efficacy in age-related hypogonadism have not been established, and revised safety information on prostate cancer and benign prostatic hyperplasia [4].
  • Labels update product by product. The AndroGel 1.62% label on DailyMed, for example, shows its cardiovascular-risk warning removed in July 2025 and still carries the age-related limitation of use [2].

What it means in practice

Three practical points follow from the guidelines and labels. Whether testosterone suits a given heart history is a clinician's call.

  • Timing after a heart event: the AUA says not to start testosterone for three to six months after a cardiovascular event [5]; the Endocrine Society recommends against it within 6 months of a heart attack or stroke and in uncontrolled heart failure [10].
  • Symptoms to report: the AUA advises men on testosterone to report chest pain, shortness of breath, dizziness or fainting at follow-up visits [5].
  • Blood pressure: labels advise periodic checks and say testosterone is not recommended with uncontrolled high blood pressure [2].
  • Lab monitoring is covered in TRT blood tests and monitoring, and hematocrit in TRT side effects.

Quick answers

Does testosterone cause heart attacks?

In TRAVERSE, the largest trial, major heart events were 7.0% on testosterone gel versus 7.3% on placebo in men at high heart risk [1]. Atrial fibrillation, kidney injury and pulmonary embolism were more common on testosterone [1].

Did the FDA remove the heart warning from testosterone?

Yes. On Feb 28, 2025 it told makers to remove boxed-warning language about increased cardiovascular risk and to add the TRAVERSE results and a blood-pressure warning [3]. Labels change product by product [2].

What changed in June 2026?

The FDA requested removal of the label statement that safety and efficacy in age-related low testosterone have not been established, plus revisions to prostate safety information [4].

Did TRAVERSE test testosterone injections?

No. It used daily 1.62% testosterone gel [1]. Injections raise hematocrit more than gels [5], which is one reason results may not transfer exactly.

Is TRT safe for men with heart disease?

TRAVERSE enrolled men with heart disease or high risk and found no increase in major heart events [1], but guidelines still advise waiting after a recent heart attack or stroke [5][10]. A clinician weighs this case by case.

More in Men's Hormones & TRT

References

  1. [1]Cardiovascular Safety of Testosterone-Replacement Therapy. N Engl J Med, 2023. PMID 37326322
  2. [2]AndroGel (testosterone gel) 1.62% prescribing information. DailyMed, U.S. National Library of Medicine, 2025.
  3. [3]FDA issues class-wide labeling changes for testosterone products (Feb 28, 2025). U.S. Food and Drug Administration, 2025.
  4. [4]Testosterone Information (updated June 23, 2026). U.S. Food and Drug Administration, 2026.
  5. [5]Evaluation and Management of Testosterone Deficiency (2024). American Urological Association, 2024.
  6. [6]Adverse events associated with testosterone administration. N Engl J Med, 2010. PMID 20592293
  7. [7]Association of testosterone therapy with mortality, myocardial infarction, and stroke in men with low testosterone levels. JAMA, 2013. PMID 24193080
  8. [8]Increased risk of non-fatal myocardial infarction following testosterone therapy prescription in men. PLoS One, 2014. PMID 24489673
  9. [9]Adverse cardiovascular events and mortality in men during testosterone treatment: an individual patient and aggregate data meta-analysis. Lancet Healthy Longev, 2022. PMID 35711614
  10. [10]Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab, 2018. PMID 29562364

Dietary supplements are not intended to diagnose, treat, cure or prevent any disease, and these statements have not been evaluated by the FDA. Prescription options need a licensed clinician. Talk to your clinician or pharmacist before starting anything new, especially if you take prescription medicines, are pregnant or breastfeeding.

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