ICD-10-CM > S00-T88 > S50-S59 > S50 > S50.8 > S50.82 > S50.821 S50.821 Blister (nonthermal) of right forearm Non-Billable/Non-Specific Codes S50.821A..., initial encounterS50.821D..., subsequent encounterS50.821S..., sequela