Semaglutide and testosterone can be linked through weight loss: low testosterone sometimes rises as men with obesity lose weight. Small studies have seen that happen during treatment. They haven't established that semaglutide directly boosts testosterone, or that it can replace treatment for a diagnosed hormone problem.
The distinction matters if a blood test has come back low. A higher number, improved sexual symptoms and better fertility are three different outcomes. The research doesn't show all three moving together.
Why weight loss can change testosterone
Obesity can suppress the signals that tell the testes to make testosterone. Doctors call this functional hypogonadism: low testosterone related to potentially reversible conditions, rather than permanent damage to the hormone system.
Semaglutide copies GLP-1, a gut hormone involved in appetite and blood sugar. It doesn't supply testosterone. When weight and blood-sugar health improve, testosterone may rise alongside them.
There is another wrinkle. Obesity can lower SHBG, a protein that carries testosterone in the blood. Total testosterone counts both protein-bound and unbound hormone. Free testosterone is the unbound portion. A low total result doesn't always mean the free portion is low too.
The Endocrine Society's guideline in The Journal of Clinical Endocrinology & Metabolism explains these distinctions. Weight-related low testosterone needs evaluation; it isn't something a medication name can diagnose.
What the semaglutide and testosterone trial found
The most direct semaglutide evidence comes from a small Slovenian trial published in Diabetes, Obesity and Metabolism in 2025. Gregorič and colleagues randomly assigned 25 men with obesity, type 2 diabetes and functional hypogonadism to semaglutide or testosterone replacement.
Thirteen received semaglutide and 12 received testosterone for 24 weeks. Everyone knew which treatment they received. Semen quality was the main outcome; testosterone was a secondary measure.
In the semaglutide group, the median total testosterone, the middle value in the group, rose from 6.1 to 7.8 nmol/L, a blood-concentration unit. The median individual increase was 1.6 nmol/L.
Those are interquartile ranges, meaning the middle half of the results, not confidence intervals estimating uncertainty around a treatment effect. The testosterone group had a larger median individual rise, 6.9 nmol/L. These treatments did not produce the same hormone response.
Semaglutide participants lost about 6.5% of their weight. The study did not establish a rise in calculated free testosterone. Sexual desire improved on one questionnaire. Erectile function, the ability to get and keep an erection, did not show a clear improvement.
The study supports a modest hormone change in this particular group. It doesn't establish the same result in men without diabetes, men with normal testosterone or people using a compounded preparation.
What other GLP-1 studies add
An earlier trial tested liraglutide, another GLP-1 medicine. Jensterle and colleagues' 2019 study in Endocrine Connections randomly assigned 30 men with obesity-related low testosterone to liraglutide or testosterone replacement for 16 weeks.
The liraglutide group lost an average of 7.9 kg and had a mean testosterone increase of 2.6 nmol/L. The reported standard deviation, a measure of variation among participants, was 3.5 nmol/L. That isn't a confidence interval, and liraglutide's result isn't a semaglutide result.
A larger medical-record study in Endocrine Practice, published online January 14, 2026, followed 215 men receiving medicines that copy gut-hormone signals. Average total testosterone rose from 332 to 399 ng/dL, another blood-concentration unit, alongside about 5% weight loss.
Larger weight losses were associated with larger testosterone gains. But this was observational: researchers reviewed existing records rather than assigning treatment by chance. It cannot prove that the medicine caused the change, and its combined results don't give a semaglutide-specific forecast.
Is it a direct drug effect?
The human studies haven't settled that question. Weight loss and better blood-sugar health are plausible explanations. The small semaglutide trial wasn't designed to separate those explanations; its authors noted the testosterone rise was smaller than expected for the weight lost, and 13 treated men cannot separate those mechanisms reliably.
As of October 1, 2026, the day this article was written, a review published September 7 in The Journal of Sexual Medicine adds a useful caution. It combined 23 randomized trials involving 1,899 men with obesity-related low testosterone across several treatment approaches. Evidence was insufficient to establish comparative testosterone benefits for GLP-1 medicines, and many comparisons had low or very low confidence.
The review's GLP-1 confidence interval, the range expressing uncertainty around its estimate, included both a decrease and an increase. That leaves the result uncertain rather than proving there is no effect. There was no direct GLP-1-versus-placebo comparison for testosterone in that evidence network.
How a clinician defines low testosterone
The Endocrine Society guideline requires compatible symptoms and consistently low testosterone, confirmed with measurements on two separate fasting mornings. A single afternoon result or fatigue alone doesn't establish the diagnosis.
When total testosterone is borderline or SHBG is altered, the clinician may also assess free testosterone. The laboratory method and its reference range matter. The evaluation also considers sleep problems, illness, medicines and possible testicular or brain-gland causes.
Semaglutide isn't a testosterone treatment. As of October 1, 2026, the day this article was written, neither Ozempic's label, “Revised: 05/2026”, nor Wegovy's label, “Revised: 06/2026”, lists low testosterone as a treatment indication, meaning an official labeled use.
For someone already prescribed testosterone, hormone care and weight-management care need a coordinated review. Semaglutide drug interactions explains why the exact medication list and route matter.
What about tirzepatide or fertility?
Tirzepatide acts on GLP-1 and GIP, another gut-hormone signal. A 2025 pilot study in Reproductive Biology and Endocrinology followed 83 men with obesity-related low testosterone in three groups. The 28 receiving tirzepatide had higher testosterone after two months. Their median total testosterone rose from 186.5 to 424 ng/dL; the middle half of final results ranged from 384 to 457 ng/dL.
This was a nonrandomized observational study, and the groups differed before treatment. It doesn't show that tirzepatide is a better testosterone option than semaglutide. Neither medicine replaces a hormone evaluation.
Fertility is a separate question. The semaglutide trial reported improved sperm shape, but it didn't measure pregnancies or live births. Testosterone replacement can suppress sperm production, so fertility goals change the clinical discussion.
For women, PCOS, a hormone condition affecting periods and metabolism, raises different questions covered in semaglutide for PCOS.
What a prescription review can answer
The useful starting points are symptoms, properly timed blood tests, weight history, diabetes status, fertility plans and current medicines. The provider assesses whether a weight-management prescription fits independently of the testosterone question. The prescriber sets the actual dose and any changes.
Through Promise, semaglutide is dispensed as a compounded medication, which is different from an FDA-approved product: the formulation offered here is not FDA-approved. Compounded means prepared by a pharmacy for a prescription. FDA's compounding explanation states that these preparations don't receive its review for safety, effectiveness or quality before sale.
A licensed provider may still prescribe a compounded formulation when appropriate; that decision is between the patient and the doctor. At Promise, a licensed provider reviews every request, and not everyone qualifies.
The hormone studies above didn't test Promise's preparation. Their findings are context for a visit, not a promised testosterone increase.
