Side effect probability calculator
Pick your drug, your current dose, and how many weeks you have been on it. We show prevalence rates from published trials and FDA adverse event reports, plus what patients have found helps and when to call your prescriber.
How the numbers work
Prevalence rates are pulled from the registration trials and post-market data for each drug. Wegovy and Zepbound prevalence numbers come from STEP (NEJM 2021), STEP-4 (JAMA 2021), and SURMOUNT-1 (NEJM 2022). T2D-indication branded drugs (Ozempic, Mounjaro, Trulicity, Victoza) use SUSTAIN, SURPASS, AWARD and LEAD-Adolescent data. Compounded products do not have dedicated trials; we use the matching branded molecule's data and flag dose-form variations from FAERS.
Numbers are point estimates from cited sources. Real prevalence varies by individual factors trials do not measure. The calculator is informational, not medical advice. Talk to a licensed clinician about your treatment.
Data sources
- STEP-1 (Wilding et al., NEJM 2021, semaglutide 2.4mg)
- STEP-2 (Davies et al., Lancet 2021, semaglutide 2.4mg in T2D)
- STEP-3 (Wadden et al., JAMA 2021, semaglutide 2.4mg + intensive behavioral)
- STEP-4 (Rubino et al., JAMA 2021, semaglutide maintenance)
- STEP-5 (Garvey et al., Nat Med 2022, 2-year semaglutide)
- SUSTAIN program (semaglutide T2D, multiple publications 2016-2019)
- PIONEER program (oral semaglutide T2D, multiple publications 2019-2020)
- SURMOUNT-1 (Jastreboff et al., NEJM 2022, tirzepatide weight loss)
- SURMOUNT-2 (Garvey et al., Lancet 2023, tirzepatide in T2D)
- SURMOUNT-3 (Wadden et al., Nat Med 2024, tirzepatide after lifestyle lead-in)
- SURMOUNT-4 (Aronne et al., JAMA 2024, tirzepatide maintenance)
- SURPASS program (tirzepatide T2D, multiple publications 2021-2022)
- SCALE program (liraglutide 3mg weight management, 2015-2016)
- LEAD program (liraglutide T2D)
- REWIND (Gerstein et al., Lancet 2019, dulaglutide CVOT)
- AWARD program (dulaglutide T2D)
- FDA prescribing labels: Wegovy, Ozempic, Rybelsus, Zepbound, Mounjaro, Saxenda, Victoza, Trulicity
- FDA Adverse Event Reporting System (FAERS) public dashboard, 2023-2025 extracts
- Cochrane systematic review on GLP-1 RA tolerability (2024)
Last compiled: 2026-05-28. Updated quarterly as new trial data and FAERS quarterly extracts publish.
