Cough and diarrhoea: what to know

A virus can irritate the airways and digestive system at the same time. COVID-19 and other respiratory infections may include gastrointestinal symptoms, while a common cold or acute bronchitis more often centres on the airways. Diarrhoea can also follow contaminated food, a medicine, or a separate stomach infection occurring alongside a cough from allergy, asthma, reflux or another condition. A cough may strain the abdomen, but that does not usually explain true loose stools. Pay attention to fever, vomiting, abdominal pain, blood or mucus in stool, breathing changes, recent travel, sick contacts and new medicines.

Take frequent sips of water or an oral rehydration drink, especially after loose stools. Eat small, plain meals when able and avoid alcohol while symptoms continue. Wash hands thoroughly with soap and water after using the toilet and before preparing food; do not prepare food for others while unwell. Rest and avoid smoke. Ask a pharmacist before using anti-diarrhoeal medicine, particularly for a child, pregnancy, fever or blood in stool. Do not start antibiotics without medical advice.

Get urgent help for severe breathing difficulty, confusion, collapse, severe abdominal pain, black or bloody stools, or inability to keep fluids down. Arrange prompt assessment for very little urine, a dry mouth with worsening weakness, persistent fever, repeated vomiting, or diarrhoea that is not settling. Infants, older adults and people with significant long-term illness can become dehydrated quickly and may need earlier advice.

Ask whether the symptoms suggest one infection or separate problems, whether a stool or respiratory test is useful, how to replace fluids, and which medicines to avoid.