Selective 5‐HT2 receptor blockade in exercise‐induced asthma

Abstract
Seven young extrinsic asthmatics participated in an open, pilot study to determine the protective effect of a selective 5‐hydroxytryptamine (5‐HT) blocking agent, ketanserin, on exercise induced asthma. ketanserin in a dose of 10 mg given intravenously 20 min before exercise altered the basal bronchomotor tone in only 1 of 6 subjects and offered partial protection against exercise‐induced bronchoconstriction in 1 of 5 asthmatics with no overall effect in the group. All patients experienced sleepiness after administration of ketanserin and one had bradycardia with hypotension. The ineffectiveness of ketanserin suggests indirectly that serotonin has a limited role in the pathogenesis of exercise‐induced asthma.