Since penicillin was originally advocated as a chemotherapeutic agent by Chain and his associates, reports have appeared in the literature on its efficacy in certain infectious diseases. Its clinical use has been reviewed by Lyons,2and more recently by Dawson and Hobby,3Herrell4and Bloomfield, Rantz and Kirby,5although no report has previously been made on its use in the treatment of bronchial asthma. The high incidence of intrinsic bronchial asthma, occurring in the young age group at this A. A. F. Regional Hospital,6led to a search for newer methods of treatment. Nine patients with intrinsic bronchial asthma were treated with penicillin. All cases were observed a minimum of four weeks before and four weeks after treatment. All cases were considered to be of moderate or severe degree in that they required emergency therapeutic measures daily (epinephrine subcutaneously or aminophylline intravenously). Seven of the