ICD-10-CM > S00-T88 > T36-T50 > T42 > T42.0 > T42.0X > T42.0X5 T42.0X5 Adverse effect of hydantoin derivatives Non-Billable/Non-Specific Codes T42.0X5A..., initial encounterT42.0X5D..., subsequent encounterT42.0X5S..., sequela