To determine the prescription characteristics of β-agonist metered-dose inhalers (MDI), we retrospectively investigated all prescriptions containing one of five types of β-agonist MDIs available at Yamagata University Hospital in 1997, as well as patients’ characteristics. The total number of asthmatic patients was 225 (age, 11-79, mean, 47.2) in 1997. Fenoterol MDI was prescribed to patients who visited the hospital at regular periods and had more severe asthma. Isoprenaline MDI also was not prescribed for first-time patients. Patients who were prescribed tulobuterol MDI had mild or moderate asthma and some of them were only occasional or first-time visitors. Salbutamol and procaterol MDIs were also prescribed for first-time patients; however, tulobuterol MDI was the most frequently prescribed for first-time patients. Patients prescribed fenoterol and isoprenaline MDIs had adequate knowledge of proper asthma management, because sufficient information had been provided about the use of MDIs in the past. Patients prescribed tulobuterol MDI should be provided with detailed instructions because they had little knowledge of handling MDIs and self-management of asthma as many of them were first or intermittent visitors. Patients prescribed salbutamol or procaterol MDIs should be evaluated regarding their past medications and some of them should be instructed regarding the use of the MDI. Although these clinical aspects might be applicable only to our hospital, the same or other prescription patterns will be found in other hospitals and/or by other physicians. Adequate instructions to individual patients who are prescribed a particular β-agonist MDI should be provided by the medical staff, especially to outpatients, to reduce hospitalization and death from asthma.