* '''Day 0:''' gradually reduce dosage of venlafaxine to a maximum of 75 mg/ day.
* '''Day 1:''' reduce a dosage of 75 mg/day to 37,5 mg/day.
* '''Day 8:''' stop administration of venlafaxine
| start =
* '''Day 1:''' simultaneously start administration of amitriptyline agomelatine in a low dosage of 25 mg/day. * '''Day 8:''' stop administration of venlafaxine and only continue administration of amitriptyline in a agomelatine. If necessary, increase dosage of agomelatine to 50 mg/day. | info = * “Start low, go slow” for amitriptyline, and caution with this switch is necessary. * Venlafaxine is a weak inhibitor of CYP2D6, which metabolizes amitriptyline.}}