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TirzepatideUp to 15mg weeklyGLP-1 + GIP~21% avg loss

Mounjaro side effects

Most side effects occur during the 20-week dose escalation and improve as your body adjusts. Here's what to expect at each dose level.

PhaseDoseCommon side effectsWhat to do
Weeks 1–42.5mgMild nausea, decreased appetiteStarting dose is usually well tolerated. Eat smaller meals.
Weeks 5–85mgNausea may increase, diarrhoeaAvoid fatty foods. Ginger tea helps nausea.
Weeks 9–127.5mgGI symptoms may peakYour doctor may extend this dose if symptoms are severe.
Weeks 13–1610mgSymptoms usually starting to improveMost people have adjusted by this point.
Weeks 17–2012.5mgMild ongoing symptomsNearly at maintenance. Side effects generally manageable.
Week 21+15mgMost GI effects have settledReport any new or worsening symptoms to your doctor.

Most common side effects

  • Nausea — most common, especially during dose increases. Usually mild-to-moderate.
  • Diarrhoea — typically improves within a few weeks at each dose.
  • Decreased appetite — intended effect but can feel uncomfortable early on.
  • Vomiting — more common at higher doses.
  • Constipation — can persist at maintenance dose. Increase fibre and water.
  • Injection site reactions — redness or itching at injection site. Rotate sites.

Serious side effects (rare)

  • Pancreatitis — sudden severe abdominal pain. Seek immediate medical attention.
  • Gallbladder problems — pain in upper right abdomen, especially with rapid weight loss.
  • Severe allergic reactions — difficulty breathing, swelling. Call 000.

Tips for managing side effects

  • Eat smaller, more frequent meals
  • Avoid high-fat and greasy foods
  • Stay well hydrated
  • Eat slowly and stop when you feel full
  • Ask your doctor about anti-nausea medication if needed

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