1. Two groups, each of 50 patients, matched according to age, sex, complications and ancillary treatments, all suffering from depressive psychoses (endogenous depressions, WHO classification 301) were treated either with amitriptyline or with imipramine and the results were compared.
2. The results after one month were better with amitriptyline, first improvement set in earlier, particularly with women, and maximal improvement was also achieved slightly earlier.
3. Patients over the age of sixty did slightly better on amitriptyline than on imipramine.
4. The difference in outcome was most marked in uncomplicated depressive psychoses, not quite so marked in cases where the depressive illness was complicated either by an organic cerebral illness or by psychogenic difficulties.
5. A list of side-effects is given. Side-effects seemed more frequent with amitriptyline than with imipramine.