The key difference
Semaglutide activates the GLP-1 receptor. Tirzepatide activates the GLP-1 receptor and the GIP receptor, another gut hormone involved in appetite and blood sugar. That dual action is why tirzepatide is often called a "dual agonist" or "twincretin".
Side-by-side comparison
| Semaglutide | Tirzepatide | |
|---|---|---|
| Works on | GLP-1 receptor | GLP-1 + GIP receptors |
| Brand-name versions | Ozempic®, Rybelsus® (diabetes), Wegovy® (weight) | Mounjaro® (diabetes), Zepbound® (weight) |
| Clinical trial weight loss* | About 14.9% over 68 weeks | Up to about 20.9% over 72 weeks (highest dose) |
| Forms at SkinnyRx | Weekly injection, daily tablet, sublingual | Weekly injection (incl. microdose), daily tablet |
| First-month price at SkinnyRx | Injection $99, tablet $149 | Injection $99, tablet $199 |
| Common side effects | Nausea, constipation, bloating | Nausea, constipation, diarrhea |
Which GLP-1 is best for weight loss?
There's no single best GLP-1 for everyone. In head-to-head and separate trials, tirzepatide produced greater average weight loss than semaglutide, but semaglutide has a longer track record, is usually cheaper and works very well for many people. The right choice depends on your health history, budget, how you tolerate side effects and whether you prefer pills or injections.
Semaglutide may suit you if…
- You want the lowest starting cost
- You'd like more pill options (tablet or sublingual)
- You prefer the medicine with the longest track record
Tirzepatide may suit you if…
- You want the option that showed the most weight loss in trials
- You didn't get the results you hoped for with semaglutide
- You're comfortable with a slightly higher monthly cost
A licensed clinician will recommend which, if either, is appropriate after reviewing your health history.
Frequently Asked Questions
Is tirzepatide better than semaglutide for weight loss?
In clinical trials, tirzepatide produced greater average weight loss than semaglutide. That doesn't make it right for everyone; a clinician weighs your history, side effects and budget.
Can I switch from semaglutide to tirzepatide?
Many people switch under medical supervision. Your clinician decides when and how to switch and what dose to start with.
Is tirzepatide available as a pill?
Compounded tirzepatide tablets are offered by some telehealth programs, including SkinnyRx. Compounded products are not FDA-approved.