Mounjaro (tirzepatide), Wegovy injection and the Wegovy pill (both semaglutide) are all licensed, prescription-only weight-loss treatments available to men through Happy Pharmacy following a free online consultation. For men specifically, the evidence also points to two additional benefits beyond the number on the scale: a reduction in visceral fat and waist circumference, and — in men whose testosterone is low because of excess weight — a documented rise in testosterone as body weight comes down. None of these medicines are licensed to treat low testosterone directly; the effect is a downstream consequence of weight loss itself.
Visceral Fat: The Type That Matters Most
Men are more likely than women to store excess weight viscerally — around and within the abdominal organs — rather than under the skin. Visceral fat is metabolically active tissue that is more strongly linked to type 2 diabetes, high blood pressure and cardiovascular disease than fat stored elsewhere on the body, which is why waist circumference is often a more useful risk marker for men than BMI alone.
Testosterone and Obesity: A Two-Way Relationship
Excess weight and low testosterone frequently occur together in men, and current clinical guidance describes this as the "pseudo-hypogonadism of obesity" — a reversible, functional drop in testosterone driven by excess weight, rather than a disorder of the testes themselves. Clinical guidance is clear that testosterone replacement is not the first-line treatment for this pattern; targeted weight loss is, because it addresses the underlying cause rather than the symptom.
This is now supported by real-world data on GLP-1 treatments specifically. In one 2025 study of 110 men with obesity or type 2 diabetes treated with semaglutide, dulaglutide or tirzepatide, an average 10% reduction in body weight was accompanied by a rise in the proportion of men with normal testosterone levels from 53% to 77% over 18 months. A separate retrospective cohort of 234 men on the same class of medicines found total testosterone rising from an average of 312 ng/dL to 368 ng/dL as body weight fell from 117kg to 108kg.
Worth knowing
These are observational, real-world findings, not results from a randomised controlled trial, and none of these medicines are licensed to treat low testosterone. The takeaway isn't that GLP-1 treatments are a testosterone therapy — it's that clinically significant weight loss, by whatever route, tends to reverse the specific, obesity-driven pattern of low testosterone described above.
All three treatments below require a prescription and a pharmacist-reviewed consultation. They work by mimicking gut hormones that regulate appetite, and all have UK licences for weight management in adults meeting the eligibility criteria.
| Mounjaro | Wegovy Injection | Wegovy Pill | |
|---|---|---|---|
| Active ingredient | Tirzepatide | Semaglutide | Semaglutide (oral) |
| How it works | Dual GIP + GLP-1 receptor agonist | GLP-1 receptor agonist | GLP-1 receptor agonist |
| How it's taken | Weekly injection | Weekly injection | Daily tablet |
| Dose range | 2.5mg – 15mg | 0.25mg – 2.4mg (7.2mg licensed) | 1.5mg – 25mg |
A 2025 head-to-head trial comparing tirzepatide and semaglutide directly (without diabetes) found tirzepatide produced significantly greater reductions in both body weight and waist circumference at 72 weeks — relevant for men specifically, given how closely waist circumference tracks cardiometabolic risk in male patients.
Why Waist Size Matters More for MenNHS and NICE guidance uses waist circumference as an additional risk marker alongside BMI, because it reflects visceral fat more directly. For men, a waist circumference of 94cm or more is associated with increased health risk, and 102cm or more with substantially increased risk — the equivalent thresholds for women (80cm and 88cm) are lower, reflecting the different way fat is typically distributed between the sexes.
| Waist circumference (men) | Risk level |
|---|---|
| Below 94cm | Low risk |
| 94cm – 101.9cm | Increased risk |
| 102cm or more | High risk |
Tracking waist circumference alongside weight can give a clearer picture of progress than the scale alone, particularly in the first few months of treatment, when visceral fat often reduces proportionally faster than overall body weight.
Rapid weight loss on any treatment — including GLP-1 medicines — involves losing some lean muscle mass alongside fat, and this is a common concern for men in particular, given testosterone's role in maintaining muscle. The steps below are general, evidence-based lifestyle measures, not medical advice specific to you — discuss any exercise or diet changes with your prescriber if you have existing health conditions.
Prioritise protein at each meal
Adequate protein intake supports muscle retention during a calorie deficit. Good sources include lean meat, fish, eggs, dairy, and plant-based options like lentils and tofu.
Keep resistance training in the mix
Strength or resistance training two to three times a week — even bodyweight exercises — gives your muscles a reason to be retained rather than lost as fuel.
Don't rush the dose escalation
Gradual dose increases, taken at the pace your prescriber recommends, tend to produce steadier, more sustainable weight loss than pushing to the highest dose as quickly as possible.
Stay in regular contact with your prescriber
Regular reviews mean any concerns about energy levels, strength or unintended rapid weight loss can be picked up and addressed early.
Mounjaro may suit you if…
- You want the option with the highest average weight loss reported in trials
- You're comfortable with a weekly injection
- Waist circumference reduction is a particular priority alongside overall weight loss
Wegovy Injection may suit you if…
- You have, or are at risk of, cardiovascular disease — semaglutide 2.4mg is licensed in the UK specifically to reduce cardiovascular risk in appropriate patients
- You want the GLP-1 medicine with the longest UK safety track record
The Wegovy Pill may suit you if…
- You'd prefer to avoid injections altogether
- You travel frequently for work and want a treatment that's simple to carry
- You can commit to a consistent morning fasting routine
Eligibility is confirmed during your free online consultation, but as a general guide you may be eligible if you have a BMI of 30 or above, or a BMI between 27 and 30 with at least one weight-related condition such as high blood pressure, high cholesterol or type 2 diabetes, and you're aged 18 or over. Final suitability always depends on your full medical history, reviewed by our GPhC-registered pharmacy team.
Important
These medicines are not suitable for everyone. They are not appropriate if you have a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2, a history of pancreatitis, or are already taking another GLP-1 receptor agonist. Always disclose your full medical history during your consultation.
Ready to Talk to a Pharmacist About Your Options?
Every treatment plan at Happy Pharmacy starts with a free online consultation, reviewed personally by our GPhC-registered pharmacy team, so you get a recommendation based on your own health history rather than a generic starting point.
Start Your Free Online Consultation → Use code SWITCH10 if you're switching from another providerHappy Pharmacy is a GPhC-registered pharmacy (No. 9012585) — Superintendent Pharmacist: Palvinder Deol — Rated 4.8★ Excellent on Trustpilot
- NHS England Digital. Health Survey for England, 2024: Adults' overweight and obesity.
- Muir CA, Wittert GA, Handelsman DJ. Approach to the Patient: Low Testosterone Concentrations in Men With Obesity. J Clin Endocrinol Metab. 2025;110(9):e3125–e3130.
- Endocrine Society. Anti-obesity medications can normalize testosterone levels in men. ENDO 2025 press release, July 2025.
- Dhindsa S, et al. Incretin-based therapies and testosterone in men: retrospective cohort. Presented at ENDO 2025.
- Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). N Engl J Med. 2022.
- Tirzepatide as Compared with Semaglutide for the Treatment of Obesity. N Engl J Med. 2025;393(1):26–36.
- NICE. Obesity: identification, assessment and management guidance — waist circumference thresholds.
- MHRA. Wegovy Summary of Product Characteristics — cardiovascular risk reduction indication.