Chronic cough guidance

Cough is very common, representing 20% of referrals to respiratory medicine, and 10% of the population at some point in life.  It is very common to not find a cause for a chronic cough; a cough present for 6 months or more is very unlikely to resolve.  Reassessment following a failure to respond to treatment is unlikely to result in a different outcome.

There are no additional treatments available for cough beyond those conditions detailed in this protocol.  Referral to secondary care is very unlikely to add anything to management in the context of normal investigations and clinical examination.

Key considerations

Acute cough, lasting less than 8 weeks, is usually associated with acute bacterial or viral bronchitis, or other respiratory infections. A new or changed cough may be the presenting symptom of a respiratory condition, particularly lung cancer.

All patients with a new or changed cough must have a respiratory examination, and a CXR. An abnormal CXR should trigger consideration of CT scanning and discussion with secondary care.

Chronic cough is a cough lasting more than 8 weeks.   The character of the cough is not helpful in differentiating the cause of the cough.  Very common triggers for chronic cough are noxious stimuli (gastric fluid, smoke, particulates, hyper- or hypo-tonicity).  A very common presentation is a chest infection that resolved with time, but the cough persisted long term, beyond the expectation for ‘post viral cough’. 

It is common to elicit a history of attacks of coughing after:

• Laughing
• Talking on the telephone
• Moving from a warm environment to a cold environment, or vice versa
• Eating
• Coming into contact with strong smells (perfumes, flowers, food aromas)

The presence or absence of these features does not help in determining the likely aetiology.

A chronic cough is usually secondary to cough hypersensitivity, a heightened response to exposure to low levels of thermal, chemical or mechanical stimulation.  The mechanisms of cough hypersensitivity are not fully understood.

Chronic Productive Cough should be investigated and managed considering the possibility of chronic bronchial infection, and bronchiectasis.

History

Obtain a detailed history focusing on:

• Possible malignancy
• Infections
• Inhaled foreign bodies
• Use of ACE inhibitors
• Reflux symptoms
• Smoking history
• Alternative respiratory illnesses

Investigations

• Clinical examination

• CXR

• Spirometry if asthma or COPD suspected

• Referral for consideration of CT is not required if the patient has a normal CXR and normal clinical examination.

If there is clinical suspicion of an underlying respiratory illness (ILD, bronchiectasis) referral to respiratory may be required for high resolution CT.

Consider most likely underlying/maintaining cause

Smoking and vaping

All patients with chronic cough who smoke, or vape, should be strongly encouraged to stop smoking and directed to smoking cessations support services.

Asthma/Eosinophilic Bronchitis

What was previously referred to as ‘cough variant asthma’, is now more commonly referred to as eosinophilic bronchitis.  The treatment is inhaled corticosteroids, to which this form of cough is usually very sensitive.  Cough may be the only presenting symptoms of the full syndrome of asthma, so a thorough history should be sought.  A predominantly nocturnal cough, and any history of wheeze and breathlessness should prompt assessment for asthma.

• Short term ICS trial
• Self-management advice
• Review at 4-6 weeks

COPD

 Cough is a common presenting complaint of COPD.  Management is: smoking cessation; LABA/LAMA with consideration of ICS; referral to pulmonary rehabilitation.

Reflux Associated Cough

The role of reflux, oesophageal dysmotility and aspiration in chronic cough is controversial.

Where previous guidance has supported an aggressive approach to acid suppression and pro-kinetic agents, the evidence base does not support their widespread use. 

High dose PPI may be trialled in patients with peptic symptoms, and/or evidence of reflux (either direct evidence at laryngoscopy, or an elevated Hull Airway Reflux Questionnaire score).  Bisphosphonates and calcium channel antagonists can worsen pre-existing reflux disease, and worsen cough.

If reflux is considered a possible cause:

• Trial of PPI (Omeprazole 20mg BD)*
• Self-management advice
• Review at 6-8 weeks

Post-Nasal Drip/Upper Airways Cough Syndrome

The role of the nose in chronic cough remains controversial.  A first-generation antihistamine, and decongestant can be trialled for 4 weeks.  Intra-nasal steroids can be helpful in some cases.

• Nasal corticosteroid
• First-generation antihistamine (e.g., Chlorphenamine, Promethazine)
• Self-management advice

Iatrogenic Cough

Chronic cough occurs in ~15% of patients taking ACE inhibitors. There is no temporal relationship between the start of ACE inhibitor treatment, and the development of cough. Any patient with a chronic cough should not receive ACE inhibitor treatment.  ARB drugs do not affect the cough reflex and should be substituted in.

If investigations detect an underlying respiratory illness, please refer to respiratory via SCI-Gateway.

Consider referral to secondary care people who have cough syncope; or people in whom cough impacts on their occupation (singers, teachers, people who rely on public speaking).

Referral to secondary care is very unlikely to add anything to management in the context of normal investigations and clinical examination.