Effect of salbutamol on smoking related cough

Smokers have an increased prevalence of chronic cough and may complain of exacerbation of cough when attempting smoking cessation. We investigated the use of smokers cough as a model for testing anti-tussive agents. The effect of salbutamol was compared with placebo in healthy adult smokers. In a randomised double blind crossover study the effect of 400 microg salbutamol via MDI plus spacer versus placebo was studied. Cough was assessed before and after the first cigarette of the day (received at 20 minutes) and throughout the day. Cough frequency, citric acid cough challenge, change in cough symptoms and peak flow were recorded. Salbutamol reduced the mean cough frequency between 0 and 20 min. A mean of 4.5 compared to 6 on placebo (p<0.05). A significant reduction in cough followed cigarette consumption in those on placebo. Mean pre-cigarette 6 compared to 3.9 post-cigarette (p<0.02). The citric acid concentration causing two coughs (C2) at 60 min increased on salbutamol. Geometric mean 278.8 compared to 190.4 mM on placebo (p<0.03). Cough frequency is reduced in smokers following a cigarette. The reduction in cough frequency and evoked cough after salbutamol suggests that beta agonists have modest activity in smoking related cough and that smokers cough represents a sensitive model to test anti-tussive activity.