Response to epinephrine in children receiving oral beta-agonists.

Physicians are sometimes concerned that the regular use of oral beta-agonists in the outpatient management of childhood asthma will result in decreased sensitivity or tachyphylaxis to these agents. While tachyphylaxis might not be clinically important during outpatient treatment, it could become significant during the emergency treatment of acute asthmatic attacks. We compared the increase in peak flow measurements before and 20 minutes after the injection of subcutaneous epinephrine hydrochloride in children with acute asthma and found no significant differences between those patients taking and those not taking oral beta-agonists.