Retatrutide
Retatrutide is an investigational drug that activates GLP-1, GIP, and glucagon receptors. It is in late-stage trials and is not approved for any use.
What it is
A once-weekly "triple agonist" peptide being developed by Eli Lilly for obesity and related conditions.
What the evidence shows
In people
A phase 2 trial published in 2023 reported large average weight loss over 48 weeks. Phase 3 trials are ongoing, and long-term safety is still being studied.
In animals and labs
Mechanism and metabolic effects were characterized in animal models before human trials.
Legal status
Investigational only. Anything sold as retatrutide outside a clinical trial is unapproved, and its identity, purity, and strength are unknown.
Dosing
There is no established human dose
No regulator has approved a dose for human use. Numbers shared online come from animal studies, small early trials, or seller protocols, and none of them have been shown to be safe or effective. BOTH does not publish dosing, mixing, or injection instructions for unapproved compounds.
Known risks
- Gastrointestinal side effects similar to other GLP-1 drugs
- Increased heart rate was reported in trials
- Unknown long-term safety
- Gray-market products may be mislabeled, contaminated, or the wrong strength