For a decade, every man who asked is TRT safe for your heart got the same answer: a boxed warning said it might not be. That warning came off in February 2025, after the largest cardiovascular safety trial ever run on testosterone reported its results. But the FDA did not simply delete a warning and walk away — it added a new one, kept a limitation that many clinics ignore, and left two signals in the data that deserve more attention than they are getting.
This article, from the clinical team at Impact Health Clinics, covers what the TRAVERSE trial actually found, what the FDA changed and what it added, and which cautions still apply. We run provider-led testosterone replacement therapy programs across four Mississippi locations with in-house labs, so these are the specific things we monitor rather than talking points.
Is TRT Safe for Your Heart? What TRAVERSE Found
The TRAVERSE trial testosterone question was designed to settle came out of a genuine scare. Several studies in 2013 and 2014 suggested testosterone therapy might raise cardiovascular risk. In 2015 the FDA responded by adding a boxed warning to every testosterone product and requiring manufacturers to run a proper trial.
TRAVERSE was that trial. It enrolled men aged 45 to 80 with low testosterone who were already at high cardiovascular risk — deliberately the population most likely to show harm if harm existed — and published in the New England Journal of Medicine in 2023.
The primary result: testosterone was noninferior to placebo for major adverse cardiac events, meaning cardiovascular death, nonfatal heart attack, and nonfatal stroke occurred at similar rates in both groups. For the specific question the 2015 warning raised, the answer was no — testosterone did not increase major cardiac events, even in high-risk men.
That is a genuinely reassuring finding, and it is why the boxed warning came off.
The Signals That Did Show Up
A trial that clears a drug on its primary endpoint can still find things on secondary ones, and TRAVERSE did. Three signals emerged in the testosterone arm:
- Pulmonary embolism — 0.9% of men on testosterone versus 0.5% on placebo
- Atrial fibrillation — higher incidence in the testosterone arm
- Acute kidney injury — also higher in the testosterone arm
These are small absolute differences, and they were not the trial's primary endpoint. They are not a reason to avoid testosterone. But they are real, they are in the published data, and a clinic that presents TRAVERSE as an unqualified all-clear is telling you only the half of it that helps them sell.
The practical implication is not "do not take testosterone." It is that a personal or family history of clotting disorders, an existing atrial fibrillation diagnosis, or compromised kidney function genuinely changes the conversation — and that someone should be asking about all three before you start.
TRT Black Box Warning Removed: What the FDA Actually Did
On February 28, 2025, the FDA issued class-wide labeling changes for testosterone products. Three things happened at once, and most coverage reports only the first.
1. The cardiovascular boxed warning language was removed. This is the headline, and it is accurate. The 2015 warning about increased risk of adverse cardiovascular outcomes is gone from the class.
2. TRAVERSE results were added to every product label. Rather than leaving a vacuum, the FDA required the actual trial findings — including the secondary signals — to appear in the prescribing information.
3. A new warning was added: testosterone can increase blood pressure. This came from TRAVERSE plus ambulatory blood pressure monitoring studies conducted after approval. It is a new warning, created in the same action that removed the old one, and it is the one most likely to matter to you personally.
So TRT black box warning removed is true but incomplete. The cardiovascular warning was replaced by a blood pressure warning, and the trial data that justified the removal was written into the label alongside it.
Two Things That Did Not Change
The FDA retained the Limitation of Use language for age-related hypogonadism. Testosterone is approved for men with hypogonadism from an established medical cause — not for men whose testosterone has simply declined with age. That distinction is widely ignored by clinics that treat any number below a reference range as a prescription trigger, and it did not change in 2025.
Topical gels also retain a boxed warning, but for something unrelated to the heart: the risk of the product transferring to another person through skin contact, which matters if there are children or a partner in the household. Different risk, different warning, still there.
TRT Side Effects Long Term: What We Actually Monitor
The TRT side effects long term question is better answered by what a clinic measures than by what it says. Testosterone therapy is safe when it is monitored and genuinely risky when it is not, and the difference is entirely in the follow-up.
What should be tracked, and why:
- Blood pressure. Now an explicit labeled warning. It should be checked at baseline and at every follow-up, not once at intake. If yours climbs, that is a dose conversation, not something to ride out.
- Hematocrit. Testosterone stimulates red blood cell production. Left unchecked, thickened blood raises clotting risk — which is plausibly related to the pulmonary embolism signal. This is the single most important routine lab in TRT and the one shortcut clinics skip most often.
- Estradiol. Testosterone aromatizes to estrogen. Both extremes cause problems, and the fix is dose management rather than reflexively adding another drug.
- PSA and prostate status. Baseline and periodic monitoring, per standard practice.
- Kidney function. Given the acute kidney injury signal in TRAVERSE, worth including in routine panels.
- Symptoms, not just numbers. The goal is how you function, not hitting an arbitrary lab target.
We run these in-house, which is why we can adjust a dose in days rather than waiting on an outside lab. Our lab panels cover the relevant markers, and our guide to TRT cost in Mississippi breaks down what monitoring actually costs — because a program priced without labs included is not a program, it is a prescription.
Who Should Be Cautious
Testosterone is not right for everyone, and the label change did not alter that:
- Men with a personal or family history of blood clots, pulmonary embolism, or deep vein thrombosis
- Men with existing atrial fibrillation or significant arrhythmia
- Men with uncontrolled hypertension — which now warrants extra attention given the new labeled warning
- Men with untreated severe sleep apnea, which testosterone can worsen
- Men with active prostate or breast cancer
- Men currently trying to conceive, since exogenous testosterone suppresses fertility
None of these are automatic disqualifications in every case. All of them require a provider who asks before prescribing.
What This Means If You Are Already on TRT
Most coverage of the label change is written for men deciding whether to start. If you are already on testosterone, three things are worth doing.
- Check when your blood pressure was last measured. The new warning postdates a lot of existing prescriptions. If your program has not taken a reading since you started, that is the gap to close first.
- Ask for your hematocrit trend, not just your last value. A single number in range tells you little. A value climbing steadily over three draws is the pattern that matters, and you cannot see it without the history.
- Revisit the indication. If you were started on the basis of a single borderline lab and no diagnosis, the Limitation of Use is worth raising with your provider — not because you should necessarily stop, but because it changes how the risk-benefit balance is weighed.
Men who started through a telehealth service and have never had a follow-up lab drawn are the group we see most often, and the fix is usually straightforward: a proper baseline, a dose adjustment, and a monitoring schedule. Our Tupelo TRT program page covers what that transition looks like in person.
Frequently Asked Questions
Did the FDA say testosterone is safe for the heart?
The FDA removed the boxed warning language about increased cardiovascular risk after TRAVERSE found testosterone noninferior to placebo for major adverse cardiac events. That is a meaningful clearance on that specific question. It is not a blanket safety declaration — the same action added a new warning about increased blood pressure.
What is the TRAVERSE trial?
A large cardiovascular safety trial the FDA required after the 2015 boxed warning. It enrolled men aged 45 to 80 with low testosterone and high cardiovascular risk, and published in the New England Journal of Medicine in 2023. It found no increase in major adverse cardiac events, with higher rates of pulmonary embolism, atrial fibrillation, and acute kidney injury in the testosterone arm.
Should the pulmonary embolism finding worry me?
It should inform your evaluation rather than frighten you. The absolute difference was small — 0.9% versus 0.5% — but it is a real signal. If you have a personal or family history of clotting, say so before starting, and make sure your hematocrit is monitored throughout.
Does TRT cause high blood pressure?
It can, and this is now an explicit warning on every testosterone product label, based on TRAVERSE plus ambulatory blood pressure studies. It does not happen to everyone. It is why blood pressure belongs in every follow-up visit rather than only at intake.
Is TRT approved for low testosterone from aging?
No, and this is the part most often glossed over. The FDA retained a Limitation of Use specifying that testosterone is indicated for hypogonadism due to an established medical condition, not for age-related decline alone. A responsible evaluation establishes an actual diagnosis rather than treating a number.
How often do I need labs on TRT?
Baseline before starting, again during the first few months as your dose is established, then periodically. Hematocrit, blood pressure, estradiol, PSA, and kidney function are the core. Any program not drawing labs on that cadence is not monitoring you.
The Bottom Line
So — is TRT safe for your heart? On the specific question the 2015 warning raised, the best available evidence says yes. TRAVERSE tested testosterone in exactly the men most likely to be harmed and found no increase in major cardiac events, and the FDA acted on that.
The honest addendum is that the same trial found higher rates of pulmonary embolism, atrial fibrillation, and acute kidney injury, that a new blood pressure warning replaced the old cardiovascular one, and that the approved indication still excludes age-related decline on its own. None of that makes testosterone dangerous. It makes monitoring the thing that separates safe treatment from a subscription.
If you want an evaluation that covers your actual history and a program where labs are part of the plan rather than an upsell, book a consult at our Oxford, Corinth, Olive Branch, or Tupelo clinic, or by telehealth anywhere in Mississippi. Our pricing page lists what everything costs — an office visit is $79, our Platinum TRT program is $249 per month including medication and provider visits, and lab panels start at $99.
This article is for educational purposes only and is not medical advice. It reflects FDA labeling and published trial evidence as of the February 2025 class-wide labeling changes; drug labeling and clinical guidance change over time, and you should verify current details with your provider and the current prescribing information. Testosterone replacement therapy carries risks and contraindications that vary by individual, including but not limited to increased blood pressure, elevated hematocrit, effects on fertility, worsening of sleep apnea, and considerations for men with a history of clotting disorders, atrial fibrillation, kidney disease, or prostate or breast cancer. Trial findings describe group averages and do not predict individual outcomes. Testosterone products are approved for hypogonadism associated with an established medical condition and carry a Limitation of Use regarding age-related decline. Any decision to begin, modify, or discontinue therapy should be made in consultation with a qualified clinician familiar with your full medical history, current medications, and lab work. Contact Impact Health Clinics to schedule a consultation.