Blister (nonthermal) of other part of head, sequela

This code signifies a non-thermal blister located on any part of the head other than the eye or eyelid, representing a residual effect or complication of a previous injury or condition. This could include blisters on the scalp, forehead, ear, nose, or cheek that are not caused by heat, cold, or chemicals.

Use this code when documenting a chronic or late-stage blister on the head, not due to thermal causes, that is a direct consequence of an earlier injury or disease process. The medical record should clearly indicate the blister's non-thermal origin and its status as a sequela, often requiring a "history of" or "due to" statement.

• Ensure documentation explicitly states the blister is non-thermal and a sequela, not an acute injury.
• Always sequence the underlying cause of the sequela first, if known and still relevant.
• Distinguish from acute non-thermal blisters (e.g., S00.81XA for initial encounter) and thermal blisters (T20.xx).