Back to Peptides
Semaglutide vs Tirzepatide
Weight LossSemaglutide and tirzepatide are the two leading FDA-approved GLP-1 based therapies for weight loss. Semaglutide (Ozempic/Wegovy) targets GLP-1 receptors alone, producing ~15% body weight loss. Tirzepatide (Mounjaro/Zepbound) is a dual GLP-1/GIP agonist that has shown up to 22.5% weight loss in SURMOUNT trials, making it the more potent option. Both are weekly injections with similar GI side effect profiles.
very high Search Demand
Side-by-Side Comparison
| Aspect | Semaglutide | Tirzepatide |
|---|---|---|
| cost | ~$900-1,350/month without insurance | ~$1,000-1,200/month without insurance |
| dosing | Start 0.25 mg weekly, titrate to 2.4 mg weekly over 16-20 weeks | Start 2.5 mg weekly, titrate to 15 mg weekly over 20 weeks |
| best for | Type 2 diabetes (Ozempic), weight loss (Wegovy), cardiovascular risk reduction | Maximum weight loss, type 2 diabetes (Mounjaro), obesity (Zepbound) |
| mechanism | GLP-1 receptor agonist — reduces appetite, slows gastric emptying, enhances insulin secretion | Dual GLP-1/GIP receptor agonist — same GLP-1 benefits plus GIP-mediated fat metabolism and insulin sensitivity |
| fda status | FDA-approved: Ozempic (diabetes), Wegovy (weight loss), Rybelsus (oral diabetes) | FDA-approved: Mounjaro (diabetes), Zepbound (weight loss) |
| weight loss | ~15% body weight (STEP trials, 68 weeks) | ~22.5% body weight (SURMOUNT-1, 72 weeks at 15 mg) |
| side effects | Nausea (44%), diarrhea, vomiting, constipation — most common during titration | Similar GI profile: nausea, diarrhea, vomiting — possibly lower nausea rates at equivalent efficacy |
Verdict
Tirzepatide produces greater weight loss (~22% vs ~15%) due to dual receptor action. Semaglutide has longer track record and more cardiovascular outcome data. Both are FDA-approved with similar safety profiles. Choice often comes down to insurance coverage and prescriber preference.