What should you know about the cause of traveller's diarrhoea?

Bacteria, viruses and parasites may be present in food, drinks, ice or water handled in unfamiliar settings. Swallowing them can irritate the intestine and change how it absorbs fluid, producing loose or watery stools, cramps, nausea or vomiting. Giardiasis is one possible parasitic cause. Food Poisoning and Gastroenteritis can look similar. Diarrhoea that began before travel, persists after returning, or follows particular foods may instead relate to Food Intolerance, Irritable Bowel Syndrome, coeliac disease, Crohn's Disease or an overactive thyroid. The timing and associated symptoms help guide assessment.

Replace lost fluid with frequent sips of safe water and oral rehydration solution when stools are frequent or vomiting is present. Eat small, simple meals as tolerated and rest. During future travel, choose sealed drinks, food served hot, and fruit that you peel yourself; wash hands before eating. Avoid preparing food for others while unwell. A clinician may recommend testing or treatment when symptoms are severe, prolonged, recurrent, or linked with a particular travel exposure.

Seek urgent care for blood in the stool, severe or persistent abdominal pain, repeated vomiting, faintness, confusion, very little urine, or signs of significant dehydration. Arrange medical advice if diarrhoea continues after travel, returns frequently, follows recent antibiotics, or affects a child, older adult, pregnant person or someone with a long-term illness. Prompt review is also sensible after travel to an area with a known outbreak.

Tell the clinician where you travelled, when symptoms began, what you ate or drank, whether others became ill, and whether there is fever, blood, vomiting or weight loss. Ask whether a stool test, rehydration plan or specific treatment is appropriate.