Health condition
Chronic cough diagnosis
A cough lasting more than eight weeks has a cause worth finding: asthma, reflux and post-nasal drip explain most cases, a medication is a classic culprit, and a systematic work-up beats years of cough syrup.
Why trust this guide
- 01
Editorial team
Written by our editorial team from the UK sources listed on each page.
- 02
Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
- 03
Current for 2026
Reviewed on 2026-09-27 with the next review scheduled for 2027-09-27.
Key facts
The essentials at a glance.
The symptoms to recognise, when to seek help, which specialist to see, and what treatment usually involves.
-
The big three causes: cough-variant asthma or eosinophilic bronchitis, acid (and non-acid) reflux, and upper airway cough syndrome (post-nasal drip)
-
Check the medicine cabinet: ACE inhibitor blood pressure tablets (names ending -pril) cause a dry cough in a significant minority - resolving weeks after switching
-
First-line tests: chest X-ray, spirometry and FeNO; treatment trials for each suspected cause are run systematically, one at a time
-
Specialist: a consultant respiratory physician; refractory cases may have cough hypersensitivity syndrome, which has its own emerging treatments
Understanding the condition
What it is and what happens next.
What causes it, how it is diagnosed, and the treatment routes available in the UK.
What it is and how it feels
Chronic cough is miserable and marginalising - the meeting interruptions, the concerned looks, the incontinence nobody mentions - and it affects far more people than clinic waiting lists suggest. After eight weeks, a cough has declared itself a condition rather than an aftermath, and the productive approach is systematic: confirm the chest X-ray is clear, stop any ACE inhibitor, then work through the dominant trio - airway inflammation (cough-variant asthma and its cousin eosinophilic bronchitis), reflux including the silent, non-heartburn variety, and post-nasal drip from rhinitis or sinusitis - with properly dosed, properly timed treatment trials.
Diagnosis and treatment routes
When each trial is given long enough (typically four to eight weeks) and assessed honestly, most chronic coughs yield; those that survive the full pathway increasingly fit the modern concept of cough hypersensitivity syndrome, where the cough reflex itself has become pathologically sensitised - explaining coughs triggered by talking, laughing, cold air and perfume. That diagnosis opens its own options: speech-and-language cough-suppression therapy has good evidence, low-dose neuromodulators help selected patients, and new targeted antitussives are reaching the clinic - so even the cough that has defeated everything has a pathway. In many parts of the UK, routine NHS referrals for this kind of problem currently take 20-45+ weeks, whereas an initial appointment with a private consultant is typically available within around two weeks.
Seeing a specialist
Who to see, and how quickly you can be seen.
The specialist for this condition is usually a consultant respiratory physician. Your GP can refer you on the NHS, or you can arrange a private consultation directly.
A quiet reminder
This guide is for information, not medical advice.
Your GP knows your history and can tell you which parts apply to you. If in doubt, see them - and seek urgent care for any of the emergency symptoms described above.
Frequently asked
Common questions about Chronic cough diagnosis.
Quick, plain-English answers to what people ask us most.
-
What counts as a chronic cough?
A chronic cough is generally defined as a cough lasting eight weeks or longer in adults (four weeks in children), persisting beyond the typical duration of a common respiratory infection. It has many possible causes and often requires a structured diagnostic approach to identify. Because the causes and appropriate treatments differ considerably, proper diagnosis matters more than simply suppressing the cough.
-
What are the most common causes of chronic cough?
The most common causes in non-smokers with a normal chest X-ray are asthma, acid reflux (gastro-oesophageal reflux disease), and upper airway conditions such as chronic rhinitis or post-nasal drip. In smokers, chronic bronchitis is also an important consideration. Multiple causes can coexist in the same person, which sometimes complicates diagnosis.
-
How is chronic cough investigated?
Investigation typically starts with a detailed history (including smoking status, medications, and associated symptoms), examination, and a chest X-ray to rule out significant lung disease, followed by more targeted tests based on the suspected cause, such as lung function tests, reflux studies, or allergy testing. A step-by-step approach, sometimes involving trial treatments for the most likely cause, is often used. This structured approach helps avoid unnecessary testing while reaching an accurate diagnosis.
-
When is a chronic cough more concerning?
Features that raise concern include coughing up blood, unexplained weight loss, a persistent change in voice, significant breathlessness, or a smoking history combined with other risk factors, since these can indicate more serious underlying conditions including lung cancer. These features generally prompt more urgent investigation, including imaging. Cough without these features, while still needing proper assessment, is much less likely to reflect a serious cause.
-
Can chronic cough be treated if no cause is found?
In some people, despite thorough investigation, no clear cause is identified (sometimes called unexplained chronic cough or cough hypersensitivity syndrome), which may relate to increased sensitivity of the nerves controlling the cough reflex. Specific treatments targeting this heightened cough reflex, alongside speech and language therapy techniques for cough control, can help in these cases. Referral to a specialist chronic cough clinic can be valuable for these more difficult-to-diagnose cases.
-
When should I see a specialist?
See a doctor if a cough persists beyond eight weeks, or sooner if accompanied by coughing up blood, weight loss, or significant breathlessness. NHS respiratory referral can take several weeks; a private respiratory consultation is typically available within about 2 weeks for a more thorough and potentially quicker diagnostic workup.