A comparative double-blind study of paroxetine and amitriptyline in the treatment of depressed hospital outpatients was undertaken at 15 centres in Italy. Three hundred and nine patients of either sex were admitted to the study. The starting dose of paroxetine was 20 mg daily and of amitriptyline 75 mg daily in divided doses; at week 3 these doses could be increased at the investigators' discretion. Efficacy was measured on the Hamilton Depression Rating Scale and on Clinical Global Impression. Both treatment groups showed significant improvement at week 6 with no significant between-group differences. Significantly fewer patients receiving paroxetine reported adverse events compared with those on amitriptyline (44% vs 62%; p < 0.01 in favour of paroxetine).