How it works
Activates both GIP and GLP-1 receptors. The added GIP activity appears to improve insulin sensitivity and lipid handling while blunting some of the nausea associated with pure GLP-1 agonism.
Structure: 39 amino acid dual GIP/GLP-1 agonist
Reported benefits
- Up to ~21% mean weight loss at 15 mg in SURMOUNT-1
- Superior HbA1c reduction versus semaglutide in head-to-head trials
- Improvements in sleep apnoea and blood pressure
Practical considerations
- Same muscle-preservation caveats as semaglutide
- Slow titration is essential
- High cost and periodic supply constraints
Side effects and risks
- Nausea
- Decreased appetite to the point of undereating
- Diarrhoea
- Rare pancreatitis
Tirzepatide dosing overview
2.5 mg weekly starting dose, escalating in 2.5 mg steps up to 15 mg
| Context | Amount | Frequency | Route |
|---|---|---|---|
| Starting dose | 2.5 mg | Weekly, 4 weeks | Subcutaneous |
| Titration steps | +2.5 mg increments | No more often than every 4 weeks | Subcutaneous |
| Maintenance | 5, 10 or 15 mg | Weekly | Subcutaneous |
This describes doses reported in published literature and community protocols. It is not a recommendation, and it is not a substitute for clinical supervision.
Tirzepatide FAQ
Is tirzepatide stronger than semaglutide?
In the head-to-head SURMOUNT-5 trial tirzepatide produced greater average weight loss than semaglutide 2.4 mg. Individual response varies widely, and side-effect tolerance often decides the practical choice.
What does dual GIP/GLP-1 agonism add?
GIP receptor activity appears to improve insulin sensitivity and may reduce the nausea burden of a given level of GLP-1 effect, though the exact contribution is still debated.
How long does titration take to reach 15 mg?
At the labelled minimum of four weeks per step, roughly 20 weeks from the 2.5 mg starting dose — and many people stop at a lower maintenance dose.
What are the most common side effects?
Nausea, diarrhoea, constipation and reduced appetite, mostly during dose increases. Pancreatitis and gallbladder events are uncommon but recognised.
Research references
- Jastreboff et al., 2022 — SURMOUNT-1, NEJM