Patients are asking if recent side effect claims with GLP-1 agonists (semaglutide, etc) are true...especially when used to lose weight.
We know GLP-1 agonists can cause GI side effects (nausea, constipation, etc). But stay informed about emerging adverse effect claims that are popping up in the news, online, etc.
Hair loss. Evidence is mixed.
Some studies show an association...NOT causation.
But know that studies didn’t account for genetic causes of some hair conditions (male pattern baldness, etc). Nutrition changes from GLP-1 therapy could also play a role in hair loss, which might be reversible.
Plus a handful of case reports and studies suggest GLP-1s may IMPROVE hair growth in some patients...and evidence is evolving.
For now, anticipate that your pharmacist will educate patients to watch for hair loss. They can also help address nutrition factors if it occurs...and weigh hair loss treatment options (minoxidil, etc) if needed.
Erectile dysfunction (ED). Rumour, with conditions.
Be aware that only a few studies suggest an increased risk of ED in men. In fact, most other studies show a DECREASED risk.
Remember that obesity and diabetes alone can affect sexual performance, so some patients may still need ED meds (sildenafil, etc).
Aspiration during surgery. Rumour, with conditions.
Some evidence suggests that peri-op patients on GLP-1s are more likely to have residual food in their stomach before surgery.
The concern is that patients could vomit this food and choke...or “aspirate”...during the procedure. Thankfully, several large studies suggest that aspiration generally does NOT happen with GLP-1s.
To be on the safe side, recent surgery guidelines prioritize holding GLP-1s for patients with high aspiration risk (Parkinson disease, etc).
Refer to our Perioperative Management of Diabetes chart to see how long GLP-1 agonists are typically held around surgery if needed.
Suicide. Rumour.
Several large studies do NOT show an increased risk of suicide with GLP-1 agonists, despite concerning initial reports.
Still alert your pharmacist ASAP if patients report mood changes, suicidal thoughts, etc...so they can get help (call 833-456-4566, etc) if needed.
Listen to our December 2025 Rumor vs Truth podcast where our editors dive deeper into the evidence behind GLP-1 side effect claims.
- Alsuwailem OA, Alanazi R, Almutairi HM, et al. Hair Loss Associated With Glucagon-Like Peptide-1 (GLP-1) Receptor Agonist Use: A Systematic Review. Cureus. 2025 Sep 16;17(9):e92454.
- Yang B, Cheng H, Hu Y, et al. Effects of Anti-Diabetic Drugs on Erectile Dysfunction: A Systematic Review and Meta-Analysis. Diabetes Metab Syndr Obes. 2025 Feb 17;18:467-478.
- Kindel TL, Wang AY, Wadhwa A, et al. Multisociety clinical practice guidance for the safe use of glucagon-like peptide-1 receptor agonists in the perioperative period. Surg Obes Relat Dis. 2024 Dec;20(12):1183-1186.
- Ebrahimi P, Batlle JC, Ayati A, et al. Suicide and Self-Harm Events With GLP-1 Receptor Agonists in Adults With Diabetes or Obesity: A Systematic Review and Meta-Analysis. JAMA Psychiatry. 2025 Sep 1;82(9):888-895.