If you're considering medical weight management, the choice usually comes down to two names: semaglutide and tirzepatide. Both are legitimate, provider-prescribed medications with strong clinical evidence. They're also meaningfully different.
How they work
Semaglutide mimics GLP-1, a gut hormone that signals fullness, slows stomach emptying, and helps regulate blood sugar. The result: you feel satisfied sooner and stay satisfied longer.
Tirzepatide does that too — and adds a second mechanism. It also activates GIP, a related hormone involved in how your body processes fat and sugar. That dual action is why tirzepatide has posted some of the strongest weight-loss results ever recorded in clinical trials.
What the results look like
In clinical trials, semaglutide users lost roughly 15% of body weight on average over 68 weeks; tirzepatide trials reported average losses of up to 20% or more at the highest doses. Individual results vary widely — genetics, dose, diet, and consistency all matter more than the label on the vial.
The best GLP-1 is the one you can stay on comfortably at an effective dose. That's a medical decision, not a leaderboard.
Side effects and dosing
Both medications share the same main side effects — nausea, digestive upset, and reduced appetite, especially during dose increases. Both are taken as a once-weekly injection and started low, stepping up gradually so your body adjusts. Some patients tolerate one noticeably better than the other, which is one more reason provider supervision matters.
Cost and access
Compounded versions from a licensed 503A pharmacy make both medications far more affordable than their brand-name counterparts. Tirzepatide typically costs more than semaglutide at equivalent stages. Before you buy either from anyone, read why the pharmacy source matters — GLP-1s are among the most counterfeited medications online.
How a provider chooses
- Your history — prior GLP-1 experience, digestive sensitivity, other medications.
- Your goal — total weight-loss target and timeline.
- Your budget — an effective dose you can sustain beats a stronger one you can't.
New to peptides in general? Start with our beginner's guide, or see the full range of benefits patients report beyond weight loss.
Explore GLP-1 options
Browse provider-prescribed peptides, shipped from a licensed 503A pharmacy.