Semaglutide and tirzepatide, as the labels describe them
Semaglutide and tirzepatide are two different molecules sold under four brand names, and almost every real difference between them is written down in their FDA-approved prescribing information. This page reports what those four documents say, quotes them where the wording matters, and marks the questions they do not answer.
Ellis Brandt built this site’s grading methodology and maintains it. Read against the labels themselves, not against secondary summaries. Last re-read 2026-09-04.
Not medical advice. Semaglutide and tirzepatide are prescription-only medicines, and whether one is appropriate for you is a question for a licensed clinician who knows your history. This page reports what the FDA-approved prescribing information says and nothing else; it is not written or reviewed by a clinician. See the medical disclaimer.
The difference in one line
Semaglutide’s labels call it a glucagon-like peptide 1 (GLP-1) receptor agonist. Tirzepatide’s labels call it a glucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist — one receptor more. Everything else on this page follows from what each label was approved to treat, not from that mechanism.
Four labels, read 2026-09-04. Versions and effective dates are printed in full at the foot of this page.
The four labels, compared
These are four separate approvals, not four names for one drug. Each row below is read from that product’s own label; nothing is carried across from another.
| Label | Active ingredient | Drug class, in the label’s words | Route and frequency | Highest dosage the label states | Initial U.S. approval |
|---|---|---|---|---|---|
| Ozempic | semaglutide | a glucagon-like peptide 1 (GLP-1) receptor agonist | Subcutaneous injection, once weekly | 2 mg once weekly | 2017 |
| Wegovy | semaglutide | a glucagon-like peptide-1 (GLP-1) receptor agonist | Subcutaneous injection once weekly; the same label also covers Wegovy tablets, taken orally once daily | Injection: a maximum of 7.2 mg once weekly, for weight reduction in adults who tolerate 2.4 mg for at least 4 weeks and for whom further weight reduction is clinically indicated. Tablets: a recommended maintenance dosage of 25 mg once daily; the label states no separate maximum | 2017 |
| Mounjaro | tirzepatide | a glucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist | Subcutaneous injection, once weekly | 15 mg once weekly in adults; 10 mg once weekly in patients aged 10 and older | 2022 |
| Zepbound | tirzepatide | a glucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist | Subcutaneous injection, once weekly | 15 mg once weekly, for all indications | 2022 |
“Initial U.S. approval” is the year printed in each label’s own highlights. It names the first approval of the active ingredient, not of that particular dosage form — which is why the oral semaglutide label also prints 2017.
What each one is approved to treat
This is where the two molecules separate in practice, and it has nothing to do with receptors. Two of these labels are diabetes labels and two are weight labels, and a reader comparing semaglutide against tirzepatide is usually comparing a brand approved for one thing against a brand approved for another.
Ozempic (semaglutide) injection
Indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus; to reduce the risk of major adverse cardiovascular events in adults with type 2 diabetes and established cardiovascular disease; and to reduce the risk of sustained eGFR decline, end-stage kidney disease and cardiovascular death in adults with type 2 diabetes and chronic kidney disease.
Wegovy (semaglutide)
Indicated in combination with a reduced calorie diet and increased physical activity, to reduce the risk of major adverse cardiovascular events in adults with established cardiovascular disease and either obesity or overweight; to reduce excess body weight and maintain weight reduction long term in adults and patients aged 12 and older with obesity, and in adults with overweight and at least one weight-related comorbid condition; and, for the injection only, for the treatment of noncirrhotic metabolic dysfunction-associated steatohepatitis with moderate to advanced liver fibrosis in adults. The label states that this last indication “is approved under accelerated approval based on improvement of MASH and fibrosis” and that continued approval “may be contingent upon the verification and description of clinical benefit in a confirmatory trial.”
Mounjaro (tirzepatide)
Indicated as an adjunct to diet and exercise to improve glycemic control in adults and patients aged 10 and older with type 2 diabetes mellitus, and to reduce the risk of major adverse cardiovascular events in adults with type 2 diabetes who are at high risk for those events.
Zepbound (tirzepatide)
Indicated in combination with a reduced-calorie diet and increased physical activity, to reduce excess body weight and maintain weight reduction long term in adults with obesity or adults with overweight and at least one weight-related comorbid condition, and to treat moderate to severe obstructive sleep apnea in adults with obesity.
Both weight labels carry a limitation of use in the same shape. Zepbound: “Coadministration with other tirzepatide-containing products or with any glucagon-like peptide-1 (GLP-1) receptor agonist is not recommended.” Wegovy: “Concomitant use of WEGOVY (semaglutide) tablets or WEGOVY (semaglutide) injection with other semaglutide-containing products or with any other GLP-1 receptor agonist is not recommended.”
What these labels do not tell you
A prescribing information document describes one product. It is not a comparison, and it is not written to be read beside another one. Three questions readers arrive with are therefore not answerable from the sources on this page, and this site will not fill them in with a plausible number.
| Question | What the labels give | Status here |
|---|---|---|
| Which molecule produces more weight reduction | Each label reports its own trials against placebo. None of the four reports a head-to-head trial of semaglutide against tirzepatide. | [needs citation] |
| Whether one is better tolerated than the other | Each label reports adverse reaction rates from its own trials and prints an explicit warning that those rates cannot be compared across drugs. | Answered as an absence on the side effect page |
| What a compounded semaglutide or tirzepatide preparation contains or doses like | Nothing. A compounded preparation has no FDA-approved label, so none of these four documents describes one. | [needs citation] |
Both markers are logged in this site’s content gap register with what would close them. A head-to-head trial read end to end would close the first; there is no document that closes the second, because the product it asks about is not one the FDA has reviewed.
Sources
| Label | Applicant on the label | SPL version | Label effective date | Where it was read |
|---|---|---|---|---|
| Ozempic (semaglutide) | Novo Nordisk Pharmaceutical Industries, LP | 20 | 2026-06-01 | DailyMed, set id adec4fd2-6858-4c99-91d4-531f5f2a2d79 |
| Wegovy (semaglutide) | Novo Nordisk Pharmaceutical Industries, LP | 19 | 2026-06-18 | DailyMed, set id ee06186f-2aa3-4990-a760-757579d8f77b |
| Mounjaro (tirzepatide) | Eli Lilly and Company | 40 | 2026-08-27 | DailyMed, set id d2d7da5d-ad07-4228-955f-cf7e355c8cc0 |
| Zepbound (tirzepatide) | Eli Lilly and Company | 40 | 2026-08-28 | DailyMed, set id 487cd7e7-434c-4925-99fa-aa80b1cc776b |
Each capture was checked against its own document title before anything was quoted from it, and a nonsense set id was fetched through the identical method in the same session as a control — it returned 404 with an empty body, so a document that returns is a document that exists.
More, read from the same labels
- Dose escalation schedulesreading the label
The starting dose, the escalation interval and the maximum dose each label sets, and why they are not interchangeable.
- Side effect ratesreading the label
What each label reports for nausea, vomiting, diarrhoea and constipation — and the sentence every label prints above those numbers.
- Missed dose rulesreading the label
The window each label gives for a late dose, and the minimum gap it requires when the injection day changes.
- Drug interactionsreading the label
Insulin and sulfonylureas, oral medications, and the oral-contraceptive precaution that appears on two of these four labels and not the other two.
- Buying one onlinereading the label
The agency's own warning signs for a telehealth GLP-1 seller, its 28-day vial rule, and what it says about drugs that arrive warm.
- Who should not take onereading the label
The boxed warning every one of these labels carries, the two contraindications, and which warnings appear on which product.