Capsaicin Inhalation Cough Challenge

Capsaicin, the pungent extract of hot pepper, is a compound of the vanilloid

class. Capsaicin induces cough in animals and man by stimulation of sensory receptors within the airways. The specific role and relative contri-

bution of the two types of afferent fibers relevant to cough, the bronchial

C-fibers and rapidly adapting pulmonary stretch receptors (RARs), remain

controversial (1,2). The recent discovery of the ‘‘capsaicin receptor,’’ the

type 1 vanilloid receptor (VR1), will likely allow further elucidation of the

mechanism of action of capsaicin (3).