The aim of this study was to compare bronchodilator response and adverse effects of terbutaline when administered with the metered dose inhaler (MDI) Bricanyl and with the dry powder inhaler Bricanyl Turbuhaler (BT). Nine adult patients with bronchial asthma participated. The study was of an open crossover design. At 30-min intervals the patients inhaled increasing doses of terbutaline (0.25 mg to 5.0 mg cumulated) from either the conventional MDI or from the BT. After each inhalation FEV1, FVC, heart rate, muscle tremor and adverse effects were recorded. Both treatments, BT and MDI, resulted in a dose-related increase in lung function, without any statistical difference. Taste sensation, muscle tremor and increase in heart rate were observed in both groups. Because of the design of the BT one may assume that inhalation failure can be avoided.