It is a reuptake-inhibitor of Serotonin and Norepinephrine, and active metabolite of Venlafaxine. It is excreted in low amount into breast milk. The amount detected in the infant's plasma is in the range of 2% - 6% respective to the amount found in the mother's plasma that is considered to be much lower than that found when the mother takes Venlafaxine. Not relevant side-effects have been found in such infants.