MHPG as a predictor of antidepressant response to imipramine and maprotiline

To explore the hypothesis that depressed patients with low pretreatment levels of urinary 3-methoxy-4-hydroxyphenylglycol (MHPG) respond more favorably to antidepressant drugs which act on noradrenergic neuronal systems than do patients with high MHPG levels, the authors administered 150--200 mg/day of imipramine or maprotiline to 13 depressed patients. All of the 5 patients with low pretreatment MHPG levels responded to treatment compared with 1 of the 14 patients with high MHPG levels; 4 patients dropped out of the study.