Inhaled verapamil in histamine-induced bronchoconstriction.
Fifteen asthmatic subjects participated in a double-blind trial comparing the protective effects of inhaled verapamil, salbutamol, and saline against inhaled histamine. Inhaling verapamil between four repeated histamine inhalation tests produced no significant protection against histamine-induced bronchoconstriction, while there was significant protection with salbutamol (p less than 0.001). Inhaling verapamil before a single inhalation test produced limited but significant protection (p less than 0.05) compared with a saline control in eight asthmatic subjects. This small protective effect in the two-treatment study of eight asthmatics suggests that either the protective effect of verapamil is variable among subjects or a preceding histamine inhalation test blocks the verapamil effect.
D000328:Adult; D001982:Bronchial Diseases / Q000139:chemically induced*; D001985:Bronchial Provocation Tests; D001986:Bronchial Spasm / Q000139:chemically induced; D003251:Constriction, Pathologic / Q000139:chemically induced*; D004311:Double-Blind Method; D005260:Female; D005541:Forced Expiratory Volume; D006632:Histamine / Q000494:pharmacology*; D006801:Humans; D008297:Male; D014700:Verapamil / Q000008:administration & dosage*
D006632:Histamine; D014700:Verapamil