Intranasal capsaicin is efficacious in non-allergic, non-infectious perennial rhinitis. A placebo-controlled study. - Blom,H.M.; Van Rijswijk,J.B.; Garrelds,I.M.; Mulder,P.G.; Timmermans,T.; Gerth,V.W. (Clin Exp Allergy, 1997)