Response to maprotiline treatment in depressive patients relationship to urinary MHPG excretion and plasma drug level.

In 20 patients with primary depression the urinary excretion of 3-methoxy-4-hydroxyphenylglycol (MHPG) was determined prior to a 4-week treatment with maprotiline 125 mg/day. Reliable data were available from 16 patients and averaged 1.35 mg/24 h. There was a trend towards a negative relationship between MHPG excretion and clinical improvement as reflected by the percent reduction in Hamilton scale scores. Responders, defined as those patients with a final score of less than or equal to 6, excreted less MHPG than partial or non-responders. Plasma maprotiline levels exhibited a significant increase between treatment days 14 and 28. They did not show a significant relationship to the reduction of total Hamilton scale scores. However, final scores of symptoms pertaining to depressive retardation were significantly higher in patients with low (less than 75 ng/ml) or high (greater than 150 ng/ml) plasma levels than in those with levels in an intermediate range.