ICD-10-CM > S00-T88 > T36-T50 > T43 > T43.1 > T43.1X > T43.1X6 T43.1X6 Underdosing of monoamine-oxidase-inhibitor antidepressants Non-Billable/Non-Specific Codes T43.1X6A..., initial encounterT43.1X6D..., subsequent encounterT43.1X6S..., sequela