1 Day 1: reduce dosage of amitriptyline to 75 mg/day. 2  Day 8: reduce dosage of amitriptyline to 50 mg/day. 3  Day 15: reduce dosage of amitriptyline to 25 mg/day. 4  Day 22: reduce dosage of amitriptyline to 10 mg/day. Day 8: reduce dosage of amitriptyline to 50 mg/day. 2  Day 15: reduce dosage of amitriptyline to 25 mg/day. 3  Day 22: reduce dosage of amitriptyline to 10 mg/day. 4  Day 29: stop administration of amitriptyline.