ICD-10-CM > S00-T88 > T36-T50 > T39 > T39.8 > T39.8X > T39.8X6 T39.8X6 Underdosing of other nonopioid analgesics and antipyretics, not elsewhere classified Non-Billable/Non-Specific Codes T39.8X6A..., initial encounterT39.8X6D..., subsequent encounterT39.8X6S..., sequela