Machine-assisted translation — the German original version is authoritative.
Metabolism & Weight
Tirzepatid
Mounjaro · Zepbound
Tirzepatide is a dual incretin agonist (GIP and GLP-1), developed by Eli Lilly and approved as a medicine for type 2 diabetes and obesity. Its use is medically supervised and prescription-only.
Regulatory status
Approved · prescription-only
Approved, prescription-only medicine — use belongs in medical hands.
Drug class
Dual GIP and GLP-1 receptor agonist
Half-life (informative)
approx. 5 days (once weekly in the approved use)
Studied in the literature
In approved preparations subcutaneous, medically supervised.
Mechanism of action
Tirzepatide simultaneously activates the GIP and the GLP-1 receptor. This dual incretin effect improves glucose-dependent insulin secretion, lowers glucagon, slows gastric emptying and reduces appetite via central mechanisms. In studies, the dual action showed in part stronger metabolic and weight effects than pure GLP-1 agonists.
The weekly administration is made possible by a fatty-acid-modified, albumin-binding structure.
Research history
Developed by Eli Lilly; approval for type 2 diabetes (Mounjaro) from 2022 and for weight management (Zepbound) from 2023. The SURPASS (diabetes) and SURMOUNT programs (obesity) form the principal evidence. For obstructive sleep apnea the regions differ: in the USA, Zepbound was specifically approved in late 2024 for moderate to severe OSA in obesity; in the EU, the responsible committee (CHMP) decided that no separate OSA indication was needed — the use is already covered by weight management, and the study data were incorporated into the product information.
Regulatory status by region
Mounjaro centrally approved for type 2 diabetes and weight management. Dispensed only on prescription.
Mounjaro (diabetes) and Zepbound (obesity/OSA). Boxed Warning regarding thyroid C-cell tumors (from animal studies).
Research areas
- Type 2 diabetes (SURPASS program)
- Obesity (SURMOUNT program)
- Obstructive sleep apnea
- Investigated in MASH and heart failure (HFpEF), among others
Documented effects (from the literature)
- Gastrointestinal effects: nausea, diarrhea, vomiting, constipation (especially during the dose-escalation phase).
- Appetite reduction and weight loss.
- Reduced appetite, early feeling of satiety.
Safety concerns & caution
- Boxed Warning (USA) regarding medullary thyroid carcinoma; contraindicated with a corresponding history or MEN-2.
- Pancreatitis and gallbladder signals.
- Risk of hypoglycemia in combination with insulin/sulfonylureas.
- Indications of reduced effectiveness of oral contraceptives — medical advice needed.
Risks of gray-market purchase
- Counterfeit and compounded tirzepatide products are a known problem.
- "Research" vials without quality control: content, purity and sterility unassured.
- Self-prepared concentrations are a common source of error.
Frequently asked questions
What does "dual agonist" mean?
Tirzepatide acts on two incretin receptors simultaneously (GIP and GLP-1), whereas semaglutide acts only on the GLP-1 receptor.
Is it "stronger" than semaglutide?
In direct studies (e.g. SURMOUNT/SURPASS comparisons), tirzepatide showed in part greater effects on weight and HbA1c. But "stronger" does not automatically mean "better for every person" — that is a medical judgment.
Are Mounjaro and Zepbound identical?
Same active ingredient, different brand names/indications: Mounjaro (diabetes), Zepbound (obesity/sleep apnea).
Is tirzepatide also approved for sleep apnea in Europe?
Here the USA and the EU differ: in the USA, Zepbound was specifically approved in late 2024 for moderate to severe obstructive sleep apnea in obesity. In the EU, the responsible committee decided that no separate sleep apnea indication was needed, because the use is already covered by the approval for weight management; the study data were incorporated into the product information.
Can tirzepatide impair the effect of the contraceptive pill?
The product information notes that the slowed gastric emptying can reduce the absorption of oral hormonal contraceptives and thus weaken their protection — especially at the start and after each dose adjustment. Anyone using oral contraception should discuss this with a physician; non-oral methods are not affected.
Sources
Primary and reference sources for your own reading.
Related substances
Unfamiliar terms? Look them up in the glossary or read the fundamentals.
This profile is for information and education only. It is not medical advice and deliberately contains no dosing or usage details. Decisions about use belong in a doctor’s hands.