How long does a stomach bug last?

Gastroenteritis can cause vomiting, loose stools, nausea, tummy cramps, fever and reduced appetite. Symptoms may arrive suddenly and gradually settle. The main concern during the illness is fluid and salt loss, especially when vomiting or diarrhoea makes drinking difficult. Rotavirus infection is one possible cause, particularly in young children. Ongoing weakness, a very dry mouth, little urine or unusual sleepiness can suggest dehydration.

Take frequent small sips of water or an oral rehydration drink. If vomiting occurs, pause briefly and restart with tiny amounts. Eat small portions when ready, choosing foods that feel easy to tolerate. Rest, wash hands with soap and water, and avoid preparing food for others while unwell. Do not use anti-diarrhoeal medicine for a child without professional advice.

Arrange medical advice if symptoms are not starting to settle, vomiting prevents drinking, or diarrhoea is persistent or bloody. Seek urgent help for severe abdominal pain, fainting, confusion, trouble waking, or signs of significant dehydration. Babies, older adults, pregnant people and anyone with a long-term illness may need advice earlier.

Ask which rehydration drink is suitable, whether medicines should be stopped temporarily, and when a child or vulnerable adult should be examined.