Tirzepatide vs Semaglutide
Written by Aaron CuhaReviewed Sep 2026
The short answer
The two most talked about weight loss drugs. One hits both the GIP and GLP-1 switches, the other hits only GLP-1. Unusually for this site, these two have been tested directly against each other in a large final stage trial. So this page can report a measured difference, not just two separate records side by side.
- Tirzepatide people
- 22,802
- Tirzepatide nulls
- 0
- Semaglutide people
- 42,363
- Semaglutide nulls
- 2
Dose
Approved titration: 2.5, 5, 7.5, 10, 12.5 and 15 mg
2.5, 5, 7.5, 10, 12.5 and 15 mg
The approved tirzepatide ladder, in mg.
Dose
Approved titration: 0.25, 0.5, 1, 1.7 and 2.4 mg
0.25, 0.5, 1, 1.7 and 2.4 mg
The approved semaglutide ladder, in mg.
First-hand reports are counted on each profile and never added together. This page sets two published records side by side. It does not pick a winner.
Column A
TirzepatideTirzepatide (dual GIP/GLP-1 receptor agonist)
A once a week shot that works on two hunger and blood sugar signals, GIP and GLP-1. In studies it led to more weight loss and lower blood sugar than drugs that work on GLP-1 alone.
Column B
SemaglutideSemaglutide (GLP-1 receptor agonist)
A once a week shot for type 2 diabetes and weight loss. It is approved, and big studies show it also lowers the risk of heart attack and stroke.
These two were tested against each other in the same trial
One trial gave people each of them. This is not us lining up two separate records.
Weight fell 20.2% on tirzepatide against 13.7% on semaglutide. Waist size fell 18.4 cm against 13.0 cm. Both gaps were clear. More people on tirzepatide reached every weight loss mark measured, at 10%, 15%, 20% and 25%. Stomach and gut problems were the most common side effects in both groups. They were mostly mild to moderate and came mainly while the dose was being stepped up.
What the trial was
A large final stage trial. Everyone knew which drug they were on. 751 adults with obesity and without type 2 diabetes were split evenly between the highest dose they could handle of tirzepatide (10 or 15 mg) or semaglutide (1.7 or 2.4 mg), weekly for 72 weeks. The main measure was the percent change in weight at week 72.
What the authors concluded
The authors state that tirzepatide beat semaglutide for cutting body weight and waist size at week 72. That is their word and their main measure, not our grade.
Where this result is weak
Everyone knew which drug they were on, including the researchers, and expecting a result can move weight. It was paid for by the maker of tirzepatide. It ran 72 weeks, so it says nothing about either drug over years. And it measured weight, not heart attacks, strokes or deaths. It also left out people with type 2 diabetes, so it does not settle the question for people who have it.
SURMOUNT-5 (NCT05822830), New England Journal of Medicine, 2025
Side by side, on the facts we can check
| What we compare | Tirzepatide | Semaglutide |
|---|---|---|
| Category | Metabolic | Metabolic |
| FDA status | FDA-approved (Mounjaro for type 2 diabetes and, from August 2026, to lower the risk of major heart and blood vessel problems in people with type 2 diabetes; Zepbound for weight management and sleep apnea) | FDA-approved (Ozempic and Rybelsus for type 2 diabetes; the Wegovy shot, the Wegovy pill approved Dec 2025, and Wegovy HD 7.2 mg approved Mar 2026 for weight management) |
| Half-life | ~5 days | ~7 days |
| Molecular weight | 4,813.5 Da | 4,113.6 Da |
| How it works | It switches on two receptors at once, GIP and GLP-1. Both answer gut hormones after a meal. Together they make the body release insulin when blood sugar is high, hold back glucagon, slow how fast the stomach empties and turn down hunger. The GIP part is thought to add its own effect on how the body handles sugar and fat. | It switches on the GLP-1 receptor, a switch on cells that normally answers a gut hormone after you eat. That makes the body release insulin when blood sugar is high. It holds back glucagon, a hormone that raises blood sugar. It slows how fast the stomach empties. It also acts on the part of the brain that runs hunger, so people eat less. |
| Studies in people | 11 | 15 |
| Evidence | Strong: 9 completed trials, 22,802 people given it | Strong: 12 completed trials, 42,363 people given it |
| Legal status, US | FDA-approved, prescription only | FDA-approved, prescription only |
Frequently asked questions
What is the difference between Tirzepatide and Semaglutide?
Tirzepatide: A once a week shot that works on two hunger and blood sugar signals, GIP and GLP-1. In studies it led to more weight loss and lower blood sugar than drugs that work on GLP-1 alone. Semaglutide: A once a week shot for type 2 diabetes and weight loss. It is approved, and big studies show it also lowers the risk of heart attack and stroke.
Which has stronger research evidence, Tirzepatide or Semaglutide?
Each compound gets a band worked out from facts we counted, with the math shown. Tirzepatide is Strong (9 completed trials, 22,802 people given it). Semaglutide is Strong (12 completed trials, 42,363 people given it). That counts how much has been done in people. It does not rate whether either one works, and neither one is called the winner.
Are Tirzepatide and Semaglutide FDA-approved?
Tirzepatide: FDA-approved (Mounjaro for type 2 diabetes and, from August 2026, to lower the risk of major heart and blood vessel problems in people with type 2 diabetes; Zepbound for weight management and sleep apnea). Semaglutide: FDA-approved (Ozempic and Rybelsus for type 2 diabetes; the Wegovy shot, the Wegovy pill approved Dec 2025, and Wegovy HD 7.2 mg approved Mar 2026 for weight management).
Related posts
Blog articles that cover Tirzepatide or Semaglutide, newest first.
- Dispatch / Sep 27, 2026 / 8 minDispatch 001: Five Retatrutide Phase 3 Trials Have Finished And None Has Posted Results
- Metabolic / Sep 27, 2026 / 8 minTesofensine Is Not a Peptide: What It Is, the Trials, and the Heart-Rate Issue
- Longevity / Sep 27, 2026 / 12 minPeptides for Longevity: What the Evidence Actually Shows in 2026
- Metabolic / Sep 27, 2026 / 10 minOral GLP-1s in 2026: Wegovy Pill vs Foundayo (Orforglipron) vs Rybelsus, and What Is Coming
Reviewed Sep 2026. This page puts two published records side by side. It is for learning, and it is not medical advice. When this site shows a dose, it is the dose a trial or a clinic actually used, or what people say they did, with the source attached. None of it tells you what to take.