If you’re researching testosterone therapy because of changes in libido, erectile function, or sexual desire, the most useful thing to understand first is this: testosterone replacement therapy (TRT) is FDA-approved for a specific diagnosis — hypogonadism, meaning the body doesn’t produce enough testosterone due to a congenital or acquired medical condition. It is not approved as a general treatment for low libido or sexual performance on its own, and the clinical evidence on how much it actually helps sexual function is more measured than most marketing suggests.
This guide lays out what the current FDA labeling actually says, what controlled trial evidence shows about sexual function specifically, where fertility risk comes into the picture, and how to tell indicated medical care apart from enhancement marketing. It’s meant to help you prepare for a conversation with a qualified clinician — not to diagnose you or recommend a product.
What Testosterone Therapy Is Actually Approved To Treat
According to the FDA, testosterone is approved solely for use in men who lack or have low testosterone levels in conjunction with an associated medical condition — in other words, a diagnosed form of hypogonadism, not simply “low-normal” levels or age-related decline on their own. Current FDA-approved formulations include oral, topical gel, transdermal patch, buccal, and injectable products.
Two things are worth understanding before anything else:
- Diagnosed hypogonadism is the approved indication. This means a clinician has confirmed low testosterone through blood testing, typically on more than one occasion, along with an identifiable or acquired cause.
- Age-related low testosterone carries a “Limitation of Use” designation. FDA’s February 2025 labeling update specifically retained limitation-of-use language for age-related hypogonadism — meaning the safety and effectiveness of testosterone therapy in men whose low levels are simply a function of aging, without an underlying diagnosed condition, has not been established to the same standard as classic hypogonadism.
This distinction matters because “I want more energy and a better sex life” and “I have diagnosed hypogonadism” are two different starting points for a medical conversation, even though they can overlap.
What Recent FDA Actions Changed — And What They Didn’t
Testosterone product labeling has moved substantially in the past two years, and it’s easy to find outdated information online. Here’s what’s actually changed:
- February 2025: Following results from the TRAVERSE cardiovascular safety trial and required postmarket blood pressure studies, the FDA removed the boxed-warning language tied to increased cardiovascular risk from all testosterone products, while adding new or expanded warnings about blood pressure increases — which the completed studies confirmed as a class-wide effect.
- April 2026: The FDA announced it is encouraging manufacturers of approved TRT products to contact the agency about potentially pursuing a new indication — treating low libido specifically in men with idiopathic hypogonadism, meaning low testosterone with no identifiable structural or genetic cause. This followed a December 2025 FDA expert panel discussion and the agency’s own preliminary review of published literature.
What this does not mean: idiopathic hypogonadism with low libido is not an FDA-approved indication today. The FDA itself describes this as an “initial step,” and it encouraged manufacturers to make contact by April 30, 2026 — any actual label expansion still requires a formal supplemental application, agency review, and substantial evidence that benefits outweigh risks in that specific population. If you see a product or clinic implying this use is already approved, that claim is ahead of where the regulatory process currently stands.
What Controlled Trial Evidence Actually Shows About Sexual Function
It helps to keep two separate testosterone trials straight, because they get conflated often in consumer coverage:
- TRAVERSE (2023) was a large cardiovascular safety trial in hypogonadal men — it’s the trial behind the 2025 labeling changes above, and it was not designed primarily to measure sexual function.
- The Testosterone Trials (TTrials), an NIH-sponsored study published in 2016, is the more directly relevant trial for this topic. It enrolled 790 men age 65 and older with confirmed low testosterone and symptoms suggestive of low androgen levels, and randomized them to testosterone gel or placebo for one year across three linked sub-trials: Sexual Function, Physical Function, and Vitality.
The TTrials results are useful precisely because they’re more measured than typical marketing claims. In the Sexual Function sub-trial, testosterone significantly improved sexual activity, sexual desire, and erectile function compared to placebo. In the Physical Function sub-trial, however, there was no significant difference in walking-distance improvement between the testosterone and placebo groups. In the Vitality sub-trial, there was no significant benefit on the primary vitality measure, though participants reported somewhat better mood and fewer depressive symptoms as a secondary finding.
The practical takeaway: the sexual-function benefit in this evidence base is real but specific — it shows up most clearly for desire, activity, and erectile function in men with confirmed low testosterone, not as a general energy or well-being boost. Testosterone therapy and erectile dysfunction medications also address different mechanisms and aren’t interchangeable; a man with normal testosterone and a primarily vascular erectile function problem is generally not a good candidate for TRT.
The Fertility Trade-Off Few People Mention
This is one of the most clinically important — and most commonly skipped — pieces of patient education around TRT, and it’s directly relevant if you’re of reproductive age or might want biological children in the future.
Exogenous testosterone suppresses the pituitary signaling (LH and FSH) that drives sperm production, which in turn lowers intratesticular testosterone — a level that needs to stay high locally in the testes for normal spermatogenesis, even while blood testosterone looks normal or high on therapy. Published clinical review literature describes this as a well-established effect that can substantially reduce or, in some men, eliminate sperm production for as long as therapy continues. The same review found that most men who stop testosterone therapy return to normal sperm production within about a year, though recovery time varies by individual and by the specific formulation used, and the long-term evidence comes mostly from contraceptive-trial populations rather than general clinical practice.
If fertility is a consideration, this is a conversation to have with a clinician before starting therapy, not after. Fertility-preserving alternatives exist — approaches that stimulate the body’s own testosterone production rather than replacing it directly — and they’re a reasonable topic to raise during evaluation rather than something to research and self-prescribe.
Indicated Care vs. Enhancement Marketing: How To Tell The Difference
Because testosterone and sexual performance are heavily marketed topics, it’s worth being clear about where the line sits:
- Indicated medical care starts with blood testing to confirm low testosterone, a clinical evaluation for an underlying cause, and prescription of an FDA-approved formulation at a monitored dose, with follow-up labs to track testosterone levels, blood pressure, and blood counts.
- Enhancement marketing typically skips diagnosis entirely, implies any man can benefit regardless of baseline testosterone level, and often blurs the line between prescription therapy and unregulated supplements. The FDA maintains notifications about sexual enhancement and energy products found to contain undisclosed active drug ingredients — products sold as “natural” or over-the-counter that actually contain hidden prescription-strength compounds not listed on the label, which is a meaningfully different risk category from a monitored prescription.
If you’re evaluating any product or program that promises improved sexual function through “testosterone support,” ask directly whether it involves an FDA-approved prescription formulation with lab monitoring, or whether it’s an unregulated supplement — the safety profile and the evidence behind each are not comparable.
Preparing For The Appointment: What To Bring
A diagnosis of hypogonadism requires lab work and a clinical history, not a symptom checklist — so the most useful thing you can do before an appointment is organize the information your clinician will actually need. Consider preparing notes on the following, for your own reference — this isn’t something to submit anywhere, it’s a private prompt list:
- Symptom pattern: What specifically has changed — libido, erectile function, energy, mood — and whether it’s constant or situational.
- Timeline: When symptoms started and whether they came on gradually or after a specific event (illness, medication change, weight change, injury).
- Current medications and substances: Prescription medications, supplements, alcohol use, and any anabolic steroid or performance-enhancing substance use, past or present — this directly affects both diagnosis and treatment safety.
- Relevant health history: Cardiovascular conditions, sleep apnea, diabetes or prediabetes, pituitary or testicular conditions, and any prior testosterone or hormone-related lab results you have access to.
- Fertility plans: Whether you are trying to conceive now or may want to in the future, since this changes which treatment approach is appropriate.
- Questions for your clinician: For example — “What specific lab values confirm hypogonadism?”, “Would this affect my fertility, and is there a fertility-preserving option?”, “What follow-up monitoring would I need?”, and “Is my symptom pattern more consistent with a testosterone issue or something else, like a vascular or psychological contributor to erectile function?”
Bringing organized answers to these points tends to produce a more accurate evaluation than describing symptoms in general terms, and it helps a clinician distinguish between a hormonal cause and other common contributors to sexual function changes.
Where This Fits If You’ve Read Our Coverage Of Pelvic-Floor And Herbal Approaches
If you came to this page from our related piece on the “Brazilian hardening secret” and erection-muscle trick, that article covers a different category entirely: pelvic-floor muscle exercise and herbal ingredients such as Tongkat Ali, which it describes as having “testosterone-modulating” properties. That’s a useful illustration of the distinction this guide is making — an herbal ingredient marketed as testosterone-modulating is not the same thing as diagnosed hypogonadism treated with an FDA-approved prescription formulation under lab monitoring. The two may both relate to sexual function, but they sit in entirely different evidence and regulatory categories, and neither substitutes for the other.
Testosterone therapy is a legitimate, monitored medical treatment for a specific diagnosis — not a general-purpose solution for sexual performance, and not something to start based on marketing claims rather than lab-confirmed need. A clinician who orders bloodwork before discussing treatment is giving you the right starting point.