Clinical perspective — cough: an unmet need

• Antitussive action of antihistamines may occur via central anticholinergic effect.
• Asthmatic cough may result from causes other than eosinophilic airway inflammation.
• A causal relationship between GERD and chronic cough remains under debate.
• Cough Hypersensitivity Syndrome has been proposed to explain chronic refractory cough.

Cough is among the most common complaints for which individuals worldwide seek medical attention. The vast majority of cases of acute cough (<3 weeks duration) are due to acute viral upper respiratory tract infection (URI) (common cold). Fortunately, acute cough is typically transient and self-limited. However, should severe and/or persistent acute cough require pharmacological treatment, satisfactory therapeutic options are scarce. Narcotic antitussives are limited by unacceptable side effects at therapeutic doses, and most over-the-counter (OTC) remedies are not supported by adequate clinical trials. The goal in chronic cough (>8 weeks duration) is to meticulously evaluate and treat all potential underlying etiologies. Despite thorough investigation, a significant minority of patients will suffer refractory, unexplained cough. For this challenging population, safe, effective, non-narcotic antitussive therapies are desperately needed.