This study compared the efficacy and safety of budesonide/formoterol (Symbicort) Turbuhaler)) with salbutamol pressurized metered-dose inhaler (pMDI) with spacer for relief of acute bronchoconstriction in patients with asthma. In this randomized, double-blind, parallel-group study, patients (n = 104 allocated to treatment; n = 103 received treatment; mean age 45 years) seeking medical attention for acute asthma (mean FEV(1) 43% of predicted) received two doses repeated at t = -5 and 0 min of either budesonide/formoterol (320/9 microg, two inhalations) or salbutamol (100 microg x eight inhalations); total doses 1280/36 microg and 1600 microg, respectively. All patients received prednisolone 60 mg at 90 min and FEV(1) was assessed over 3h. FEV(1) 90 min after dosing (primary variable) increased compared with pre-dose FEV(1) by an average of 30% and 32% for budesonide/formoterol and salbutamol, respectively (P = 0.66), with similar increases at all timepoints from 3 to 180 min for both groups. Mean pulse rate over 3h was significantly higher in the salbutamol group versus the budesonide/formoterol group (92 vs. 88 bpm; P < 0.01). No treatment differences were seen for other vital signs, including ECG. High-dose budesonide/formoterol was effective and well tolerated for the treatment of acute asthma, with rapid onset of efficacy and a safety profile over 3h similar to high-dose salbutamol.