* '''Day 8:''' simultaneously start administration of duloxetine in a normal low dosage of 30 mg/day.* '''Day 15:'''increase the dosage of duloxetine to 60 mg/day.| info =* {{theorSS}}Occurrence of serotonin syndrome is theoretically possible, so caution is necessary.* Duloxetine is a inhibitor of CYP2D6, which metabolizes vortioxetine.}}