Can Mounjaro cause dehydration?

Yes—Mounjaro can contribute to dehydration, mainly because common side effects like nausea, vomiting, and diarrhoea can lead to fluid loss if not managed promptly. Dehydration risk is higher if these symptoms are severe or persistent, and warning signs can include dark urine, dizziness, and feeling faint. UK guidance from pharmacy services emphasises keeping well hydrated, using oral rehydration solutions if needed, and seeking medical advice if unable to keep fluids down or if diarrhoea lasts more than a couple of days. In rare cases, severe dehydration can strain the kidneys, so it’s important to act early and contact NHS 111 or a GP if symptoms escalate.

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