Why do weight-loss injections cause nausea?

How slower stomach emptying causes nausea on Wegovy and Mounjaro, and what helps.

GLP-1 and dual-agonist medicines slow stomach emptying, which can cause nausea, fullness, reflux and sometimes vomiting, especially when the dose is increased. Eating smaller meals, cutting back on fatty or greasy foods and drinking enough water can help. Speak to your prescriber if vomiting is severe or you can't keep fluids down.

This is general information about prescription medicines, not advice or a recommendation to use them. Speak to your prescriber or pharmacist about your own treatment.

Sources we checked

  1. Semaglutide (Wegovy, Ozempic) (NHS)
  2. Tirzepatide (Mounjaro) (NHS)

This article is general information, not medical advice. Speak to a doctor, pharmacist or other qualified clinician about your own health, especially before starting a supplement or if symptoms are new, severe or worrying.

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