What to do about sickness and diarrhoea on holiday

Travel can expose you to unfamiliar germs, unsafe water or food that has been poorly stored. Food poisoning and gastroenteritis may cause sudden vomiting, loose stools, cramps and fever. Giardiasis can cause longer-lasting diarrhoea, bloating and unpleasant-smelling stools after contaminated water or food. Food intolerance, irritable bowel syndrome, coeliac disease, Crohn's disease or an overactive thyroid can also cause diarrhoea, particularly when symptoms continue after the trip. The timing, associated symptoms and duration help a clinician narrow the cause.

Take frequent small sips of safe water or an oral rehydration drink. Eat light foods when able and avoid alcohol; wash hands carefully and do not prepare food for others while unwell. A pharmacist can advise on suitable medicines, especially if you are pregnant, have a long-term condition or take regular medication. Keep a note of when symptoms began, recent meals, water exposure, fever and any blood in the stool.

Get urgent medical help for blood or black stool, severe abdominal pain, repeated vomiting that prevents drinking, fainting, confusion, very little urine, marked weakness or a high fever. Seek medical advice if symptoms persist after returning home, recur, or affect a child, older adult or person with a weakened immune system.

Ask whether you need stool testing, how to replace fluids safely, whether travel-related parasites are possible, and when it is safe to return to work or prepare food.