What should you know about intestinal stomach flu?

Despite the nickname, gastroenteritis is not the same illness as influenza. Viruses are a common cause, although bacteria, parasites, contaminated food or water, and close contact with an infected person can also be involved. Rotavirus infection is one possible cause, particularly in children.

The main concern is fluid and salt loss from vomiting or diarrhoea. Dehydration may show as a dry mouth, dark or reduced urine, dizziness, unusual sleepiness, or difficulty keeping fluids down. Loss of appetite is common for a short time, but fluids remain a priority.

Take frequent small sips of water or an oral rehydration drink. If vomiting occurs, pause briefly and restart with small amounts. When appetite returns, choose simple foods you tolerate and continue drinking. Rest, wash hands carefully with soap and water, and avoid preparing food for others while unwell.

Do not give children or vulnerable adults medicines for diarrhoea or vomiting without professional advice. A pharmacist can advise whether an oral rehydration product is suitable and whether any regular medicine needs special handling during the illness.

Get urgent medical help for severe or worsening abdominal pain, blood or black material in stool or vomit, confusion, fainting, marked drowsiness, or signs of significant dehydration. Contact a clinician promptly if you cannot keep fluids down, symptoms are not settling, or the person affected is a young child, an older adult, pregnant, or living with a condition that increases dehydration risk.

Ask: How can I replace fluids safely? Are my symptoms consistent with gastroenteritis or another cause? Should I be tested or treated for an infection? Which medicines should I avoid or pause? How can I reduce the chance of passing it to people at home?