Semaglutide Side Effects in Men: Libido, Testosterone and Safety

Short answer: The most common semaglutide side effects in men are the same as in women: nausea, diarrhea, vomiting, constipation and stomach pain, mostly when the drug is started or the dose goes up. Less common but serious risks include pancreatitis, gallbladder problems, kidney injury from dehydration and a boxed warning about thyroid C-cell tumors seen in rodents. Reports of lower libido or erection problems exist, but the evidence so far is weak and mixed, and losing excess weight may actually help hormones in many men. If your drive or erections change on a GLP-1 medicine, talk to your prescriber rather than stopping or adding products on your own.

Key Takeaways

• In the Wegovy (semaglutide 2.4 mg) trials, nausea affected 44% of adults versus 16% on placebo, diarrhea 30% versus 16% and vomiting 24% versus 6%.^[2]
• Serious but uncommon risks include acute pancreatitis, gallstones, acute kidney injury from fluid loss and low blood sugar when combined with insulin or sulfonylureas.^[1][2]
• Semaglutide is not used in men with a personal or family history of medullary thyroid carcinoma or MEN 2.^[2]
• A 2025 analysis of FDA adverse event reports found 182 male sexual dysfunction cases tied to GLP-1 drugs, and the authors concluded overall patient risk remains low.^[4]
• Muscle loss comes from rapid weight loss itself, so protein intake and strength training matter during treatment.^[5]
• Tell your prescriber and pharmacist about every supplement you take, including herbal products such as Panax ginseng.^[1][7]

What Semaglutide and Other GLP-1 Medicines Do

GLP-1 receptor agonists copy a natural gut hormone called glucagon-like peptide 1. According to Cleveland Clinic, this hormone triggers insulin release, blocks glucagon, slows stomach emptying and increases the feeling of fullness. Slower digestion reduces blood sugar spikes, and the appetite effect reduces how much people eat, which often leads to weight loss.^[3]

Semaglutide is sold as Ozempic (weekly injection for type 2 diabetes), Rybelsus (daily tablet for type 2 diabetes) and Wegovy (for weight management). Tirzepatide (Mounjaro, Zepbound) is a related dual GLP-1 and GIP agonist. Cleveland Clinic notes that higher doses tend to produce stronger effects, which is one reason doctors raise the dose step by step.^[3]

Mayo Clinic describes eligibility for prescription weight loss drugs as a BMI above 30, or above 27 with a serious weight related condition, along with prior attempts at diet and exercise. It also warns about compounded versions of semaglutide and tirzepatide, which are not tested for safety or effectiveness, and advises filling prescriptions at a state licensed pharmacy.^[6]

Semaglutide Side Effects in Men: What the Label Shows

There is no separate list of side effects for men. The official prescribing information applies to everyone, and the numbers below come from the Wegovy label on DailyMed (adults on the 2.4 mg injection unless stated otherwise).^[2]

Stomach and digestive effects

MedlinePlus lists nausea, vomiting, diarrhea, stomach pain, constipation, heartburn, burping, headache and runny nose or sore throat as common effects, and asks patients to tell their doctor if any are severe or do not go away.^[1] Cleveland Clinic adds that these effects are more likely when you start the medication or move to a higher dose.^[3] For many men, this phase is also when energy and interest in sex dip, simply because they feel unwell and are eating very little.

Gallbladder, pancreas and kidneys

The label lists acute gallbladder disease, acute pancreatitis and acute kidney injury due to volume depletion as warnings.^[2] MedlinePlus describes pancreatitis warning signs as ongoing pain in the upper left or middle stomach that may spread to the back, with or without vomiting, and gallbladder warning signs as upper stomach pain, yellowing of the skin or eyes, fever or clay colored stools.^[1] Repeated vomiting or diarrhea can dehydrate you, which is why decreased urination or swelling of the legs, ankles or feet should be reported.

The thyroid C-cell boxed warning

Semaglutide carries a boxed warning because it caused dose and duration dependent thyroid C-cell tumors in rodents. It is not known whether this applies to humans. The drug is contraindicated in people with a personal or family history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia syndrome type 2 (MEN 2).^[2] MedlinePlus advises calling a doctor right away for a lump or swelling in the neck, hoarseness, trouble swallowing or shortness of breath.^[1]

Heart rate, low blood sugar and anesthesia

The label reports a mean resting heart rate increase of 1 to 4 beats per minute. Low blood sugar is mainly a concern in men who also take insulin or a sulfonylurea. There are also rare reports of pulmonary aspiration during general anesthesia or deep sedation, so tell your surgeon or dentist that you use semaglutide.^[1][2]

Ozempic and Testosterone, Libido and Erections

This is the part men search for most, and it is also where the evidence is thinnest. Keep two questions separate: what the drug might do directly, and what weight loss and illness do around it.

What the adverse event data say

A 2025 study in the International Journal of Impotence Research looked at the FDA Adverse Event Reporting System from late 2003 to early 2024. It found 182 male cases of erectile dysfunction, decreased libido or orgasmic dysfunction linked to GLP-1 receptor agonists. Most men were 40 to 60 years old, diabetes was the most common reason for treatment (43.9%), and exenatide (24.2%) and semaglutide (21.4%) accounted for the most reports.^[4]

The reporting odds ratio was 0.41, below 1, and the authors concluded that monitoring is needed as GLP-1 use expands, “though overall patient risk remains low.”^[4] Adverse event databases collect voluntary reports. They cannot prove that a drug caused a problem, and they do not tell you how often it happens.

Why weight loss can work in the other direction

Many men who take GLP-1 medicines start with obesity, type 2 diabetes or both, and these conditions are widely associated with lower testosterone and with erection problems in their own right. Losing a meaningful amount of excess weight is generally seen as favorable for hormone balance and blood vessel health. Whether semaglutide changes testosterone directly, beyond the effect of weight loss, is still being studied. If you want facts instead of guesses, ask your doctor for a morning blood test and compare your result with the normal testosterone levels for your lab.

Practical reasons drive can dip during treatment

• Feeling sick: nausea, reflux and fatigue in the first weeks leave little room for desire.
• Very low intake: eating far less than before can lower energy and mood.
• Dehydration: vomiting and diarrhea can leave you lightheaded and drained.
• Other medicines: blood pressure drugs, antidepressants and diabetes treatment can all affect sexual function. See our guide to metformin and testosterone if you also take metformin.
• Underlying conditions: diabetes, vascular disease and sleep apnea can affect erections whether or not you take a GLP-1 drug.

Persistent erection problems can be an early sign of heart or blood vessel disease. That is a reason to see a doctor, not to self treat.

Muscle Loss With Rapid Weight Loss

Cleveland Clinic explains that GLP-1 drugs do not directly cause muscle loss; losing weight does, and fast, large weight loss can contribute to sarcopenia, a loss of muscle mass, strength and function.^[5] For men, losing muscle can mean less strength, a slower metabolism and less energy, all of which can feed into lower drive.

Cleveland Clinic suggests a general guideline of 0.8 to 1 gram of protein per kilogram of body weight per day, adjusted for age, activity and goals, ideally with help from a registered dietitian. It also recommends strength training with weights or resistance bands, noting that you may see improvements in muscle within two to three months of consistent training, along with losing weight gradually and staying hydrated.^[5] Our guide on how much protein men need shows how to spread protein across smaller meals when appetite is low.

Mayo Clinic also notes that many people regain some weight after stopping these drugs, so building habits during treatment matters for the long run.^[6]

Who Should Avoid Semaglutide or Talk to a Doctor First

Only your prescriber can decide whether semaglutide is right for you. Raise these points before starting or if you are already on it:

• Personal or family history of medullary thyroid carcinoma or MEN 2 (contraindicated).^[2]
• History of pancreatitis, gallbladder disease or kidney disease.^[1]
• Diabetic retinopathy or other eye problems if you have type 2 diabetes.^[2]
• Use of insulin or sulfonylureas, which raise the risk of low blood sugar.^[3]
• Planned surgery or sedation.^[1]
• Any vitamins, nutritional supplements and herbal products you take or plan to take.^[1]

Get urgent care for severe ongoing belly pain, signs of an allergic reaction (rash, swelling of the face or throat, trouble breathing) or inability to keep fluids down.

Supplements While on a GLP-1: Tell Your Prescriber

No supplement is a substitute for a prescribed GLP-1 medicine, and none should be used to manage its side effects without medical advice. MedlinePlus specifically asks semaglutide users to tell their doctor and pharmacist about all vitamins, nutritional supplements and herbal products.^[1]

This matters for herbs that may influence blood sugar. NCCIH states that some evidence suggests Asian ginseng (Panax ginseng) might lower blood sugar levels and that it might interact with certain medications.^[7] If you take a product that contains Panax ginseng, including Ultra Bann, show the full label to your prescriber before combining it with semaglutide, especially if you also use insulin or a sulfonylurea. The complete Ultra Bann label, with every botanical and its amount, is on the ingredients page, and you can read more about this herb in our Panax ginseng guide.

Frequently Asked Questions

Does Ozempic cause erectile dysfunction?

It has not been shown to. Voluntary FDA reports include some cases of erectile dysfunction and low libido in men on GLP-1 drugs, but a 2025 analysis concluded overall patient risk remains low, and such reports cannot prove cause.^[4] Diabetes, vascular disease and other medicines are common contributors, so discuss any change with your doctor.

Does Ozempic lower testosterone?

There is no clear evidence that it does. Obesity and type 2 diabetes are linked with lower testosterone, and weight loss is generally considered favorable for hormone balance. If you have symptoms, ask for a morning testosterone test rather than guessing.

Do semaglutide side effects go away?

Digestive side effects are most likely at the start and after dose increases, and Mayo Clinic notes common mild effects may get better over time.^[3][6] Tell your doctor if symptoms are severe or persistent.^[1]

How can men avoid losing muscle on a GLP-1 drug?

Eat enough protein (Cleveland Clinic cites 0.8 to 1 gram per kilogram per day as a general guide), lift weights or use resistance bands regularly, lose weight gradually and stay hydrated.^[5]

Can I take herbal supplements with semaglutide?

Only after checking with your prescriber or pharmacist. Some herbs, such as Panax ginseng, may lower blood sugar, which matters if you also take other glucose lowering drugs.^[1][7]

References

1. Semaglutide Injection. MedlinePlus Drug Information, U.S. National Library of Medicine.
2. WEGOVY (semaglutide) prescribing information. DailyMed, U.S. National Library of Medicine.
3. GLP-1 Agonists. Cleveland Clinic.
4. Pourabhari Langroudi A, et al. Male sexual dysfunction associated with GLP-1 receptor agonists: a cross-sectional analysis of FAERS data. International Journal of Impotence Research. 2025;37(8):661 to 667.
5. Can Ozempic Cause You To Lose Muscle? Cleveland Clinic Health Essentials, 2025.
6. Prescription weight-loss drugs. Mayo Clinic.
7. Asian Ginseng. National Center for Complementary and Integrative Health (NCCIH).

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. This article is for information only and is not medical advice.