Ep. 33 - GLP-1 Side Effects Patients Are Actually Reporting and What Reddit Data Reveals

Dr. Tim Sayed walks through an April 2026 study published in Nature that analyzed over 410,000 Reddit posts from people using semaglutide and tirzepatide, using AI language models to extract and categorize what patients were actually saying about their experiences on these medications. The study identified roughly 67,000 self-reporting users, and among them, 43.5% described at least one side effect, with nausea leading at 37%, followed by fatigue, vomiting, constipation, and diarrhea.What makes this study notable, and what Sayed spends real time on, is where the real-world data diverges from the clinical trial record. Fatigue appeared far more commonly in Reddit posts than in formal trial reporting. Reproductive symptoms including irregular periods, mid-cycle bleeding, and heavy cycles emerged as a signal in about 4% of users reporting any side effect, something not well captured in current drug labeling. Temperature-related complaints like chills and hot flashes showed up as well, which the study authors connected speculatively to glucagon's known role in thermogenesis. Sayed is careful to carry the study's own caveats: selection bias is real, Reddit skews younger and American, and voluntary self-reporting cannot establish true prevalence.The broader point he lands on is practical. Prescribers should know what patients are reading and talking about, because those conversations are already shaping what people expect and ask about in the clinic.Contact Dr. Tim Sayed:Phone: (858) 247-2933Email: [email protected]: timsayedmd.comInstagram: @timsayedmdYouTube: @TimsayedmdFacebook: Tim Sayed MD