Research

Hormonal

Retatrutide increases the rate of gastrointestinal adverse events (nausea, vomiting, constipation) and hypersensitivity reactions compared to placebo, but does not significantly increase serious adverse events.

Be aware that retatrutide is more likely to cause nausea, vomiting, and constipation than a placebo. However, these are typically not 'serious' adverse events, and the drug does not appear to increase the risk of serious health complications or death compared to no treatment. Monitor your symptoms and communicate with your doctor.

GoodQualifiesMEDIUM confidence
Compared with placebo, retatrutide significantly increased the rate of TEAEs (RR 1.18; 95 % CI 1.04–1.35; p = 0.01; I2 = 0 %; Supplementary Material 1, Fig. S5A), nausea (RR 2.68; 95 % CI 1.54–4.68; p < 0.01; I2 = 0 %; Supplementary Material 1, Fig. S5B), vomiting (RR 4.59; 95 % CI 1.30–16.24; p = 0.02; I2 = 0 %; Supplementary Material 1, Fig. S5C), constipation (RR 3.08; 95 % CI 1.12–8.45; p = 0.03; I2 = 0 %; Supplementary Material 1, Fig. S5D), and hypersensitivity (RR 3.79; 95 % CI 1.20–11.96; p = 0.02; I2 = 0 %; Supplementary Material 1, Fig. S6A). There was no significant difference between groups for serious adverse events (RR 1.46; 95 % CI 0.46–4.61; p = 0.52 I2 = 49 %; Supplementary Material 1, Fig. S6B).
Eric Pasqualotto et al. · Metabolism Open · 2024

Why this rating

Based on 3 RCTs with low heterogeneity for most adverse events (I2=0%) and low risk of bias.

Source

Effects of once-weekly subcutaneous retatrutide on weight and metabolic markers: A systematic review and meta-analysis of randomized controlled trials

Eric Pasqualotto et al. · Metabolism Open · 2024

DOI 10.1016/j.metop.2024.100321

Meta-analysis · 3 studiesCited 12×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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