Bronchodilator therapy for chronic cough.

Experimental studies indicate that airway calibre increases the sensitivity of the afferents involved in the cough reflex but it has proved difficult to demonstrate that airway calibre increases the sensitivity of the afferents involved in the cough reflex. Therefore, bronchodilators might have a role, although rather minor, in the treatment of cough. However, although bronchodilators represent the standard of care in the treatment of airway obstruction associated with asthma or COPD, controversy persists regarding the mechanism(s) by which these agents alleviate cough. Furthermore, the available evidence indicates that the effects of bronchodilators on cough are rather inconsistent in humans and casts doubt on the appropriateness of the common practice of using bronchodilators in the treatment of patients with cough without any other evidence of airway obstruction. Regrettably, appropriate long-term trials specifically aimed at evaluating the clinical efficacy of bronchodilators in pathologic cough have not yet been performed. Therefore, properly executed clinical studies of bronchodilators in various types of acute and chronic pathologic cough are required.