Alcohol-induced bronchospasm in an asthmatic patient: pharmacologic evaluation of the mechanism.

A 23-year-old Asian with histamine-reactive asthma complained of recurrent chest tightness, nasal congestion and flushing immediately after drinking minimal amounts of alcoholic beverages. He was extensively studied to determine the possible mechanism of his alcohol-induced respiratory symptoms. Drinking of either beer or 95 percent ethanol in apple juice immediately provoked vasomotor signs and moderately severe bronchospasm (54 percent and 73 percent decreases in specific airway conductance, respectively), which spontaneously improved over 30 minutes and two hours, respectively. Intravenous and inhaled ethanol caused less bronchospasm than observed with oral ethanol, and recovery was rapid. Pretreatment with cromolyn sodium (inhaled or oral) and isoproterenol had no inhibitory effect on the alcohol-induced bronchoconstriction, whereas atropine, acetylsalicylic acid, cyproheptadine, and chlorpheniramine appeared to have a partial inhibitory effect. Approximately 70 percent inhibition was observed after chlorpheniramine. Observations in this patient suggest that the bronchoconstriction induced by alcoholic beverages is related to their ethanol content and may be related to formation or release of one or more bronchoconstrictor and vasoactive compounds, including a stimulant of histamine1-receptors. The route of ethanol administration may also influence the bronchospastic response.