How they differ
Semaglutide mimics GLP-1, a gut hormone that signals fullness, slows stomach emptying and improves blood sugar. Ozempic is licensed for type 2 diabetes, and Wegovy (up to 2.4 mg) for weight management. Tirzepatide (Mounjaro) adds a second hormone, GIP, which seems to add to the effect.
What the trials show
- SURMOUNT-1: tirzepatide gave about 15 – 21% average weight loss over 72 weeks, depending on dose
- STEP-1: semaglutide 2.4 mg gave about 15% average weight loss over 68 weeks
- SURMOUNT-5 (head-to-head): about 20% with tirzepatide vs about 14% with semaglutide
- SELECT: semaglutide reduced heart attacks, strokes and cardiovascular deaths by 20% in people with heart disease
Side effects
Both commonly cause nausea, constipation or diarrhoea, especially when doses increase. Slow titration helps. Neither is suitable in pregnancy, or for people with a personal or family history of medullary thyroid cancer or MEN2. Tirzepatide can make oral contraceptive pills less reliable, so a backup method is advised after starting and after each dose increase.
Cost in India
Generic semaglutide arrived in India after the patent expired in March 2026, lowering costs significantly. Mounjaro remains a branded product. We'll discuss current options at your consultation.
Our view
There's no universally better drug. We choose based on your BMI, diabetes status, heart risk, side-effect tolerance and budget, and then protect your muscle, skin and hair through the journey. See our slimming programme.
This article is for general education and is not medical advice. Results vary from person to person.