Journal of Depression and Anxiety
Open Access

Abstract

No Changes in Plasma Level of 3-Methoxy-4-Hydroxyphenylglycol after Switching Paroxetine to Milnacipran in Patients with Major Depressive Disorder: A Preliminary Study

Reiji Yoshimura, Hikaru Hori, Asuka Katsuki, Atsuko Ikenouchi-Sugita, Wakako Umene-Nakano, Kiyokazu Atake and Jun Nakamura

We investigated the plasma levels of 3-methoxy-4-hydroxyglycol (MHPG) in patients who failed to paroxetine treatment and switched to milnacipran. The aim of the present study is to predict responders to serotonin noradrenaline reuptake inhibitor (SNR) who were resistant to selective serotonin reuptake inhibitor (SSRI) based on the plasma MHPG levels. The HAMD17 scores decreased from 17.0 ± 2.2 to 9.5 ± 2.5 after 4 weeks of milnacipran treatment. Eight of 20 (40%) patients were responded 4 weeks after milnacipran treatment. Five of 20 (25%) became remission. Plasma MHPG was changed neither in responders (from 4.9 ± 0.7 ng/ml to 5.6 ± 0.8 ng/ml) (t=-1.604, p=0.132) nor in nonresponders (from 5.1 ± 1.3 ng/ml to 5.3 ± 1.2 ng/ml) (t=-0.363, p=0.719). No difference was found in the change of plasma MHPG before and 4 weeks after milnacipran administration in two groups (t=1.894, p=0.073). These results suggest that the change of plasma MHPG level was not related to the improvement when switching from paroxetine to milnacipran.