Patients attending the emergency room with acute asthma, participating in a study comparing salbutamol (albuterol in the United States) via a dry powder inhaler (Turbuhaler) with pressurized metered-dose inhaler (pMDI), were included in this 1-week follow-up study with the aim of assessing whether inhaled budesonide via Turbuhaler may be an alternative to prednisolone tablets after an acute asthma attack. Eighty-one patients with a mean age of 38 years and forced expiratory volume in 1 sec (FEV1) of 64% predicted normal value after treatment with salbutamol were randomized in this double-blind, double-dummy, parallel-group study. The doses given were budesonide 1600 microg b.i.d. or prednisolone in daily doses from 40 mg (day 1) decreased to 5 mg (day 7). FEV1 was recorded before and after the 7-day treatments and peak expiratory flow (PEF) morning and evening, clinical symptoms (visual analogue scale 0-100), and doses of rescue medication (terbutaline Turbuhaler 0.25 mg/dose) were recorded daily. The mean increase in FEV1 from baseline to day 7 was 17.3% in the budesonide Turbuhaler group and 17.6% in the prednisolone group. Mean values of morning PEF increased from day 1 to day 7 by 67 L/min in the budesonide Turbuhaler group and by 57 L/min in the prednisolone group (not significant). There were no statistically significant differences between the groups in clinical symptoms and in the number of doses of rescue medication. Because of disease deterioration, five patients in the Turbuhaler group and three in the prednisolone group needed additional symptomatic as well as corticosteroid treatment. Inhaled budesonide in high doses may be a substitute for oral therapy as follow-up treatment after an acute asthma attack.