Persistent cough

Category: Lungs & Breathing · All lungs & breathing symptoms

What it can feel like

A persistent cough is one that lasts more than eight weeks in an adult (four in a child) or keeps returning. By this stage it is unlikely to be a simple passing infection, and it deserves a structured look at the common culprits — airways, sinuses, reflux, medicines and smoking.

Possible causes

A symptom can have many causes, and most are not serious. The lists below group conditions this symptom can be associated with — common causes first. They are possibilities to discuss with a clinician, not a diagnosis.

Common causes

A persistent cough can be associated with post-nasal drip, asthma and allergy, heartburn reflux, smoking or vaping, and the dry cough caused by ACE-inhibitor blood pressure medicines.

Other possible causes

A persistent cough can also be associated with chronic bronchitis, bronchiectasis, scarring lung conditions, heart failure, tuberculosis and, less commonly, lung cancer — which is why a chest X-ray is a standard early step.

Red flags — when to seek help promptly

Coughing up blood, however little
Persistent cough with unexplained weight loss or night sweats
A hoarse voice lasting more than three weeks alongside the cough
Persistent cough in someone who has smoked, with a change from their usual cough

What a clinician may do

A clinician will examine your chest and ears, nose and throat, review your medicines, and usually arrange a chest X-ray and lung function tests. Swapping a suspect medicine, treating reflux or airway inflammation, and referral to a chest clinic follow the findings.

Watch: related videos

Examination and clinical videos from the MedicalVideos.com library relevant to this symptom. Some clinical footage is graphic — that is the nature of a medical video library.

▶ WatchChronic coughWatch on MedicalVideos.com ▶ WatchUsmle step 2 cs chronic coughWatch on MedicalVideos.com

Related guides on MedicalVideos.com

Frequently asked questions

Can reflux really cause a cough?

Yes — acid reaching the upper airway irritates it and triggers coughing, and the cough itself can worsen reflux. It is one of the three classic causes of persistent cough alongside post-nasal drip and asthma, and treating it can settle a cough that has lasted months.

Should I just try another cough mixture?

Over-the-counter mixtures can soothe, but a cough present beyond three weeks — and certainly beyond eight — has earned a proper assessment with a chest examination and usually an X-ray, rather than another bottle.

Related symptoms — Lungs & Breathing

Breathlessness Bringing up phlegm Chest infections that keep coming back Cough Coughing up blood Noisy breathing

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Please note: This page is educational information about a symptom. A symptom alone cannot diagnose any condition, and the causes listed here are possibilities, not a diagnosis. If you are worried about a symptom — especially one that is new, severe, getting worse or not going away — please see your own clinician, who can examine you and arrange tests. In an emergency, call your local emergency number.