A cough that will not go: causes and tests

What causes a cough that lasts?

The NHS cough page lists smoking, heartburn (acid reflux), allergies and infections such as bronchitis as causes. NHS guidance describes asthma, bronchiectasis, acid reflux and postnasal drip as causes of a long-lasting cough. Some NHS hospital trust leaflets list ACE inhibitors, a type of blood pressure medicine, as a cause of a long-lasting cough. NHS inform says a persistent cough is often of unknown cause. The NHS says bronchitis often gets better without treatment in around 3 weeks. A chest infection usually gets better on its own in about 7 to 10 days, although the cough and mucus can last up to 3 weeks. Antibiotics are generally not used for viral chest infections such as flu or viral bronchitis.

What can help at home?

The NHS says most coughs can be managed at home with rest and fluids, and a pharmacist can advise on cough medicines. A local NHS self-care leaflet says there is little evidence on whether over-the-counter cough medicines relieve symptoms.

When should a cough be seen by a GP?

The NHS advises seeing a GP if a cough has lasted more than 3 weeks, if weight is being lost for no reason, or if the immune system is weakened. A South East London Cancer Alliance page urges people with a persistent cough to contact their GP. The NHS lung cancer symptoms page lists symptoms including chest or shoulder pain, weight loss without trying, and tiredness.

When is a cough urgent?

The NHS advises an urgent GP appointment or a call to NHS 111 for a cough with chest pain or a feeling of being very unwell. The NHS cough page advises an urgent GP appointment or NHS 111 for coughing up blood or finding it hard to breathe, and the NHS bronchitis page says to call 999 if someone is struggling to breathe, for example choking or gasping and unable to speak. For people with bronchiectasis, the NHS says to call 999 if more than a few streaks of blood are coughed up.

What does the GP do?

A GP may listen to the chest. NHS inform says a GP may arrange tests such as a chest X-ray, breathing or lung function tests, and a sample of phlegm. NHS pages say antibiotics are not usually prescribed for coughs, and a GP may refer people to a specialist if the cause is unclear.