A cough has several possible causes. Persistent or worsening symptoms warrant professional advice. Breathing difficulty, chest pain or coughing blood need urgent attention. This overview does not diagnose infection or recommend an antibiotic. Severe breathing difficulty or severe chest symptoms require emergency care. Coughing blood, becoming very unwell or a persistent cough warrants prompt assessment. A clinician may consider TB and other causes using history and tests; cough alone cannot diagnose TB. Mention weight loss, night sweats, fever or known exposure. Routine cough advice must not delay care or be used to choose antibiotics.