Twenty-one pediatricians specializing in allergy, pulmonology, or both were questioned about their use of adrenergic bronchodilators for treating children of different ages at home, in the emergency department, and in the hospital. Most would use inhaled medications in all settings and for all ages. Few expressed strong preference for one drug over another, but only 2 would regularly use nebulized isoproterenol hydrochloride or isoetharine hydrochloride. Dosing frequency of inhaled medication at home was usually limited to every 4 hours, but in the emergency department or hospital, intervals between doses of 20 minutes or less were common. If this treatment failed, 9 physicians would use intravenous isoproterenol, but 4 strongly opposed its use. These results indicate that substantial variation exists in current expert practice, but that inhaled albuterol, metaproterenol, or terbutaline sulfate are most often preferred for treating asthma, bronchopulmonary dysplasia, and bronchiolitis in children of all ages, and that doses and dosing intervals are frequently altered to meet patient needs.