Inhibition of methacholine-induced bronchoconstriction with reproterol, a new beta agonist-xanthine derivative

This study compared the efficacy of single oral doses of a new beta adrenergic agonist-xanthine derivative, reproterol, with placebo by measuring the degree of induced bronchodilation and inhibition of response to methacholine challenge in patients with bronchial asthma. In comparison with placebo, 30 mg reproterol was an effective bronchodilator. Attenuation of the response, but not complete blockage of the methacholine-induced bronchoconstriction, was observed with 30 mg reproterol. Methacholine-induced bronchoconstriction is of use in assessing effect and mechanism of the action of new pharmacologic agents.