In order to investigate the efficacy of pharmaceutical instruction including the instructions for use of a metered dose inhaler by inpatients with chronic bronchial asthma, intervals of hospital visits, therapeutic scores in the prescription and in the consulting room were assessed in twelve patients who were treated at Yamagata University Hospital. No patients who re-entered the hospital were recognized after their discharge from the hospital (12.8-30.4 months). The mean times of exacerbation needed for the intra-venous injection of steroids and/or aminophylline during the one year period before and after the last hospitalization in which pharmaceutical instructions were given, were 2.8 and 1.6, respectively. One of the 12 patients received the injections for treatment of asthma only one time during the one year period. In seven patients who received oral corticosteroids at discharge, three patients were able to discontinue and two patients were able to decrease their dosage. Although it was difficult to obtain any specific contribution ratio on their clinical efficacy, the pharmaceutical service including usage instruction of the metered dose inhaler by pharmacists to the patients with bronchial asthma was found to be useful especially for patients who had been repeatedly hospitalized.