ICD-10 Code L66.11 – Classic lichen planopilaris (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L66.11 – Classic lichen planopilaris
What it is
L66.11 identifies classic lichen planopilaris, a scarring inflammatory disorder that affects hair follicles on the scalp. It is used when the diagnosis is specifically documented in the record.
Clinical signs
Typical findings include patchy scalp hair loss with perifollicular redness, scale, and signs of permanent follicle damage. Clinical features vary; refer to documentation.
When to use this code
Use this code when the clinician documents classic lichen planopilaris as the confirmed diagnosis. It is appropriate for records describing scarring alopecia with follicular inflammation on the scalp. If the note only says hair loss or alopecia without subtype, check documentation.
Do not use for
Do not use this code for nonscarring alopecia, unspecified alopecia, or other forms of cicatricial alopecia unless classic lichen planopilaris is documented. Check documentation.
Coding tip
Code the most specific hair-loss diagnosis documented; “scarring alopecia” alone is not enough for L66.11.