Diarrhoea for a week: what to know

An infection may be lingering, or the bowel may be reacting to a food, medicine, or underlying condition. The clinician may ask about travel, water, antibiotics, diet, stress, fever, pain, blood, nighttime symptoms, and weight change. Possibilities include gastroenteritis, giardiasis, coeliac disease, food intolerance, inflammatory bowel disease, or thyroid overactivity; symptoms alone cannot confirm any one of them.

Book a routine appointment soon, sooner if symptoms are worsening. Drink regularly, use oral rehydration solution when appropriate, and choose nourishing foods you can tolerate. Avoid alcohol and do not make a major gluten-free diet change before coeliac testing unless a clinician advises it, because this may affect test interpretation. Keep a diary of stools, meals, medicines, and associated symptoms.

Seek urgent care if you develop blood or black stools, severe abdominal pain, persistent vomiting, fainting, confusion, or very little urine. Fever with marked weakness also warrants prompt assessment. Arrange earlier review if you have a long-term illness, take immune-suppressing medicine, are pregnant, or are treating a child or older adult.

Ask whether you need stool or blood tests, whether any medicine could be contributing, and which foods and drinks will support recovery without hiding useful diagnostic clues.