ICD-10-CM > S00-T88 > T36-T50 > T46 > T46.5 > T46.5X > T46.5X6 T46.5X6 Underdosing of other antihypertensive drugs Non-Billable/Non-Specific Codes T46.5X6A..., initial encounterT46.5X6D..., subsequent encounterT46.5X6S..., sequela