What is a chronic cough?

• A cough lasting 8 weeks or greater is a chronic cough.

• Cough is a natural reflex to clear our airways, and we need it to survive. However some people can develop an exaggerated cough reflex which can be be very troublesome.

What are the top 4 causes?

1. If asthma or "twitchy airways" (post-infection bronchial hyperresponsiveness) is suspected?

• 3 month trial

• Very common - typically begins with infection symptoms e.g. acute onset cough, purulent sputum, malaise, fever. Patient gets better but cough persists, for several months. Eventually settles, some patients may have very mild asthma unmasked by infection, others just have post infection bronchial hyperresponsiveness (easier to term “twitchy lungs” with patients!)

• Recovery often faster if treated with asthma medication e.g Relvar 92/22 1 puff once daily, gargling after use, with inhaler technique check. 

• Grampian inhaler guidelines on www.aberdeenlungs.com if you want to use alternatives.

• Reinforce the fact that the inhaled steroid component will not have maximal effect until 4-6 weeks of regular use. Anecdotally by adding in a long acting bronchodilator this provides some rapid onset benefit. If prescribed only low dose beclomethasone many patients will try it for a week and then give up, since on benefit perceived. 

• If patient prefers a pressurised metered dose inhaler (pMDI) e.g Fostair always use with a spacer. Spacers doubles lung deposition - otherwise most of the drug won’t get past your patient’s tongue. 

• Review at 2-3 months. If cough is gone stop the inhaler. If cough then recurs then the patient may have asthma. 

2. If reflux ("indigestion / heartburn") is suspected?

• 3 month trial

• Omeprazole 20mg twice daily AND gaviscon 5mls four times daily.

• Rationale - Omeprazole negates gastric acid acidity but patients can still reflux neutral fluid - even if this only affects the distal oesphagus it results in neuronal activation triggering a reflex cough. An alginate such as Gaviscon acts as a floating “barrier.”

• General advice - avoid eating late at night e.g. after 8pm, avoid foodstuffs and drinks that reduce lower oesphageal tone e.g. chocolate, cheese, caffeine, alcohol.

• Exercise and diet to promote achieving a healthy weight. 

3. If post-nasal drip is suspected?

• 3 month trial

• Check nasal spray technique

• Nasal corticosteroid e.g Nasonex 2 sprays each nostril once daily.+/- antihistamine e.g Dymista.

• Nasal saline e.g NeilMed, Sterimar

4. If neurogenic (nerve related) cough is suspected?

• If there is no response to any of the above treatment trials then neurogenic cough should be considered.

• 3 month trial of treatment suggested.

• The evidence base for treatment is limited but the sorts of drugs that can be tried include:

  • Nortryptiline: 10mg at bedtime increasing by 10mg each week to maximum 40mg at night.

  • Gabapentin

    • Days 1-3: 300mg at bedtime

    • Days 4-6: 300mg at lunch and bedtime (600mg total dose)

    • Days 7-9: 300mg at breakfast, mid-afternoon, bedtime (900mg total dose)

    • Days 10-12: 300mg at breakfast, lunch, dinner, bedtime (1200mg total dose)

    • If no improvement in cough after reaching 1200mg daily then probably no merit increasing further.