* '''Day 115:''' simultaneously start administration of doxepin in a dosage of 25 mg/day. * '''Day 8:''' stop administration of venlafaxine and continue administration of doxepin.| info = * “Start low, go slow” is not required, but caution is necessary.* Venlafaxine is a weak inhibitor of CYP2D6, which metabolizes doxepin.}}