Plasma levels and clinical response with imipramine in a study comparing efficacy with mianserin and nomifensine.

1 The comparative antidepressant efficacy of 150 mg imipramine, 60 mg mianserin and 150 mg nomifensine was studied in 45 depressed patients in a six week double-blind investigation. 2 In the efficacy analysis of 41 patients completing the study there was no overall significant difference in efficacy between the groups. Individual group comparisons showed no significant difference in response between mianserin and nomifensine, and mianserin and imipramine. There was a significant (z = 1.99, P less than 0.05) improved response in the imipramine compared with the nomifensine treated group. The imipramine treated group were significantly older. 3 No significant plasma concentration/clinical response relationships were demonstrated with nomifensine, mianserin, imipramine or desipramine. 4 Plasma level monitoring of imipramine recommended by some investigators does not seem to be appropriate.