People on Reddit are reporting "hidden" side effects of Ozempic and Mounjaro, like random chills and changes to their periods.
medRxiv · March 13, 2026 · 10.64898/2026.03.12.26348253
Why it matters
By tracking hundreds of thousands of real-world patient experiences on social media, researchers identified significant reproductive and temperature-regulation symptoms that were never listed on official drug labels or captured in clinical trials. This highlights a gap between the controlled testing of blockbuster weight-loss drugs and their bizarre real-world biological effects.
From the abstract
Social media can reveal patient experiences with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) that extend beyond clinical trial data. We analyzed 410,198 Reddit posts (May 2019-June 2025) mentioning semaglutide or tirzepatide. A total of 67,008 users self-reported using these medications, and 43.5% described at least one side effect. Gastrointestinal symptoms predominated, including nausea (36.9%), fatigue (16.7%), vomiting (16.3%), constipation (15.3%), and diarrhea (12.6%). Notably, r