tirzepatide
Mounjaro (tirzepatide) is an injectable dual GIP and GLP-1 receptor agonist from Eli Lilly. It improves blood sugar control in type 2 diabetes alongside diet and exercise, and in the European Union it is also approved for weight management in adults with obesity or overweight with a weight-related condition.
This page is based on the EMA medicine record for tirzepatide, cross-checked with the Health Canada product record for Mounjaro; the mechanism is explained in plain language, and analogies are used only where they stay accurate.
How it works
Explains what the medicine does in the body, not dosing, side effects, or safety.
An analogy
After a meal the gut sends hormone notes that help the body handle the incoming food. In type 2 diabetes and obesity those notes are ignored or fade too fast. Tirzepatide is a long-lasting double copy of two such notes, GIP and GLP-1. The pancreas releases insulin on time, the liver stops dumping sugar, food leaves the stomach more slowly, and the brain feels fuller, so blood sugar settles and weight tends to fall.
In simple terms
Tirzepatide is given by injection and activates the receptors for two natural gut hormones, GIP and GLP-1. Together these signals help the pancreas release insulin when blood sugar is high, reduce the release of glucagon, and slow the movement of food out of the stomach. In the brain the same signals reduce appetite and caloric intake. These effects improve blood sugar control in type 2 diabetes and support weight loss and weight maintenance when combined with a reduced-calorie diet and increased physical activity.
In depth
Tirzepatide is a dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist. By activating both incretin receptors it enhances glucose-dependent insulin secretion from pancreatic beta cells, suppresses glucagon secretion, slows gastric emptying, and reduces appetite and food intake centrally. In type 2 diabetes mellitus it improves glycaemic control as monotherapy or in addition to other diabetes medicines, and it is also approved in the European Union for chronic weight management in adults with obesity, or overweight with at least one weight-related comorbidity, alongside lifestyle measures.
See it in motion
A schematic animation of the mechanism — simplified for clarity, not drawn to scale.
How GIP/GLP-1 co-agonists work
- The body's own incretin hormones GIP and GLP-1 work through their receptors in several tissues.
- The drug activates both incretin receptors.
- Insulin release rises in a glucose-dependent way while glucagon secretion falls, and gastric emptying slows.
- Blood glucose and body weight both trend downward over time.
Target: Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors
Receptors for two gut hormones released after meals; activating both boosts glucose-dependent insulin release, suppresses glucagon, slows stomach emptying, and reduces appetite and caloric intake.
Approved uses
Approved uses differ by country and change over time. Always follow your local prescribing information.
Approved uses in European Union
EMA- For the treatment of adults, adolescents and children aged 10 years and above with insufficiently controlled type 2 diabetes mellitus as an adjunct to diet and exercise, as monotherapy when metformin is considered inappropriate due to intolerance or contraindications, or in addition to other medicinal products for the treatment of diabetes
- As an adjunct to a reduced-calorie diet and increased physical activity, for weight management including weight loss and weight maintenance in adults with an initial Body Mass Index of 30 kg/m2 or more (obesity), or of 27 kg/m2 to less than 30 kg/m2 (overweight) in the presence of at least one weight-related comorbid condition such as hypertension, dyslipidaemia, obstructive sleep apnoea, cardiovascular disease, prediabetes, or type 2 diabetes mellitus
Official sources
The statements on this page trace back to these records.
- Mounjaro (tirzepatide) — Summary of product characteristics and package leaflet, English version
European Medicines Agency
- U.S. Food and Drug Administration: tirzepatide prescribing information
U.S. Food and Drug Administration
This page explains how the medicine works — it isn’t the patient leaflet. For anything that applies to you, read the leaflet that came with your medicine or ask your pharmacist.
MedUnfold provides educational content and is not medical advice. Always follow your local prescribing information and healthcare professional.