Tirzepatide vs semaglutide dosage for weight loss, compared: starting doses, titration steps, maximum doses, and head-to-head trial results at 72 weeks.
Tirzepatide and semaglutide are dosed on completely different scales, and no formula converts one into the other. Tirzepatide for weight loss starts at 2.5 mg once weekly and titrates up to a maximum of 15 mg, while semaglutide for weight loss starts at 0.25 mg once weekly and tops out at 2.4 mg. Both are increased slowly over several months and are intended to be used alongside diet and physical activity.
Tirzepatide Dosage for Weight Loss (Zepbound)
Zepbound is the FDA-approved brand of tirzepatide for chronic weight management in adults. The dose rises in 2.5 mg increments, and each step is held for at least four weeks.
- 2.5 mg once weekly for 4 weeks — a starting dose to test tolerability, not a weight-loss dose.
- 5 mg once weekly for at least 4 weeks — the first dose that produced meaningful weight loss in clinical trials.
- 7.5 mg, 10 mg, and 12.5 mg once weekly — each step lasts at least 4 weeks.
- 15 mg once weekly — the maximum approved dose for weight loss.
Your prescriber may keep you at a lower dose if you are losing weight steadily or having side effects. The highest tolerated dose is not automatically the best dose.
Mounjaro contains the same active ingredient and is approved for type 2 diabetes. Questions about tirzepatide vs mounjaro for weight loss usually come down to insurance coverage and labeling rather than chemistry.
Tirzepatide pens are single-dose, so there is nothing to calculate. Compounded vials are a different situation. Because concentrations vary by pharmacy, a tirzepatide dosage calculator for weight loss can help you convert milligrams into units on a syringe, but a prescriber or pharmacist should confirm every number.
Semaglutide Dosage for Weight Loss (Wegovy)
Wegovy is the FDA-approved semaglutide product for chronic weight management. It follows a fixed five-step titration spread across roughly 16 weeks.
- 0.25 mg once weekly for 4 weeks
- 0.5 mg once weekly for 4 weeks
- 1 mg once weekly for 4 weeks
- 1.7 mg once weekly for 4 weeks
- 2.4 mg once weekly — the maintenance and maximum dose
Steps can be stretched beyond four weeks when side effects are rough. Some people reach their goals at 1.7 mg and never move higher.
Oral semaglutide is a different product
Rybelsus is oral semaglutide approved at 3 mg, 7 mg, and 14 mg daily for type 2 diabetes. It is not approved for weight loss. If you see a semaglutide tablet dose for weight loss listed somewhere online, confirm that it matches the prescription written for you rather than a diabetes tablet, because the two are not the same plan. Newer oral weight-loss formulations have been studied at higher daily doses, so verify what is actually FDA-approved before assuming a tablet will match an injection.
Dosage Comparison: Tirzepatide vs Semaglutide
If you prefer to see the steps in one place, the table below doubles as a tirzepatide dosage chart for weight loss and a Wegovy titration guide.
| Titration step | Tirzepatide (Zepbound) weekly dose | Semaglutide (Wegovy) weekly dose |
|---|---|---|
| Weeks 1-4 | 2.5 mg | 0.25 mg |
| Weeks 5-8 | 5 mg | 0.5 mg |
| Weeks 9-12 | 7.5 mg | 1 mg |
| Weeks 13-16 | 10 mg | 1.7 mg |
| Weeks 17-20 | 12.5 mg | 2.4 mg (maintenance) |
| Week 21 and beyond | 15 mg (maximum) | 2.4 mg (maximum) |
Both schedules assume the medication is tolerated. Missing doses or pausing treatment for several weeks can mean restarting at a lower step.
Does a Higher Dose Mean More Weight Loss?
Up to a point, yes, and the effect is larger for tirzepatide in the published trials.
| Drug and dose | Average weight loss | Trial |
|---|---|---|
| Tirzepatide 5 mg | about 15% | SURMOUNT-1, 72 weeks |
| Tirzepatide 10 mg | about 19.5% | SURMOUNT-1, 72 weeks |
| Tirzepatide 15 mg | about 20.9% | SURMOUNT-1, 72 weeks |
| Semaglutide 2.4 mg | about 14.9% | STEP 1, 68 weeks |
| Tirzepatide vs semaglutide 2.4 mg | 20.2% vs 13.7% | SURMOUNT-5, 72 weeks |
These numbers are averages, not promises. Individual results vary widely, and some people respond better to semaglutide than to tirzepatide. Trial data, not dose numbers, is what answers tirzepatide vs semaglutide which is better for weight loss.
You Cannot Convert One Dose Into the Other
Semaglutide is a GLP-1 receptor agonist. Tirzepatide is a dual GIP and GLP-1 receptor agonist. They target different receptors, have different potency per milligram, and were studied at independent dose ranges.
- There is no approved conversion ratio between the two drugs.
- Switching usually means restarting at the lowest dose of the new medication, even from the highest dose of the old one.
- Stacking the two or splitting doses is not supported by evidence and raises the risk of severe gastrointestinal side effects.
Safety and Side Effects to Expect
Most side effects appear during titration and ease as the body adjusts. Common complaints include nausea, vomiting, diarrhea, constipation, and abdominal pain.
Both medications carry a boxed warning about thyroid C-cell tumors observed in rodents. They are not recommended for people with a personal or family history of medullary thyroid cancer or MEN2 syndrome.
Other risks include pancreatitis, gallbladder disease, and dehydration-related kidney injury. Both are contraindicated during pregnancy, and both suppress appetite, so protein intake and nutrition deserve attention.
Anyone considering these medications should review their full medical history with a licensed healthcare professional before starting, switching, or changing a dose. Never adjust your dose based on someone else's schedule or a social media post.
Frequently Asked Questions
What is the starting dose of tirzepatide vs semaglutide for weight loss?
Tirzepatide (Zepbound) starts at 2.5 mg once weekly, and semaglutide (Wegovy) starts at 0.25 mg once weekly. Both starting doses are designed to let the body adjust rather than to produce weight loss. The dose is typically increased every four weeks until a maintenance dose is reached.
Can I switch from semaglutide to tirzepatide at the same dose?
No. There is no conversion formula between semaglutide and tirzepatide, and the two drugs are measured on unrelated milligram scales. Prescribers usually restart patients at the lowest dose of the new drug and titrate up again. Switching without medical guidance can cause severe nausea, vomiting, and dehydration.
Which is stronger for weight loss, tirzepatide or semaglutide?
In the head-to-head SURMOUNT-5 trial, tirzepatide produced about 20.2% average weight loss versus 13.7% for semaglutide at 72 weeks. That does not mean tirzepatide is right for everyone, since individual response, side effects, cost, and insurance coverage all matter. Both are FDA-approved for chronic weight management.
This page provides educational research information and does not replace medical advice, diagnosis, or treatment.