The most effective weight-loss drugs ever made — and the new triple-agonists about to surpass them.
GLP-1 receptor agonists are the most effective pharmacological weight-loss tools ever developed. Semaglutide (Ozempic, Wegovy) produces 15–18% mean weight loss over 68 weeks. Tirzepatide (Mounjaro, Zepbound), which activates both GLP-1 and GIP receptors, achieves 22% over 72 weeks. Retatrutide — a triple agonist hitting GLP-1, GIP, and glucagon — has shown 24% at 48 weeks in Phase II and is the current frontier.
But the dosing schedule, side-effect calculus, and muscle-preservation strategies vary materially across the class. This hub is the entry point — pick a compound below to read its full guide.
Ozempic · Wegovy · Rybelsus
The original GLP-1. Mature data, well-characterized side effects, predictable dosing.
Mounjaro · Zepbound · LY3298176
Dual GLP-1 / GIP agonist. FDA-approved. The current weight-loss benchmark.
LY3437943 · Triple-G
Triple-agonist in Phase III. ~24% weight loss at 48 weeks.
| Semaglutide | Tirzepatide | Retatrutide | |
|---|---|---|---|
| Receptors | GLP-1 | GLP-1 + GIP | GLP-1 + GIP + GCG |
| Max wt-loss | ~15-18% | ~22% | ~24% (Ph II) |
| Trial dose | 2.4 mg / wk | 15 mg / wk | 12 mg / wk |
| Status | FDA approved | FDA approved | Phase III |
| Half-life | ~7 days | ~5 days | ~6 days |
Retatrutide has produced the largest weight loss in clinical trials (~24% at 48 weeks in Phase II), followed by tirzepatide (~22% at 72 weeks). Semaglutide produces ~15–18% over 68 weeks. Retatrutide is not yet FDA-approved.
In head-to-head trials (SURMOUNT-5), tirzepatide produced significantly greater weight loss than semaglutide. However, side-effect profiles, costs, and availability differ. Choose based on goals, tolerance, and access.
Discontinuation studies show most patients regain a significant portion of lost weight within 1–2 years off-drug. GLP-1s are typically managed as long-term metabolic therapy, similar to blood-pressure medication.
Yes — many users switch from semaglutide to tirzepatide for stronger weight loss, or downward when supply is constrained. Switching requires a brief washout and re-titration to manage GI side effects.
Epti is the first training app built around your peptide protocol — workouts, dosing, side-effects, and bloodwork on one timeline.