Effect of intranasal capsaicin on symptoms and mediator release.

Differential nasal responsiveness to environmental tobacco smoke (ETS) has been documented in humans and we hypothesized that this reflects differential responsiveness to c-fiber stimulation. We compared the response to intranasal capsaicin in subjects with and without a history of ETS-rhinitis. We challenged 10 ETS-sensitive and 11 ETS-nonsensitive subjects intranasally with 25 mg of lactose powder followed by 25 pg to 25 ng of capsaicin in 25...