ICD10
ICD-10 Code L66.1: Lichen planopilaris
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Diseases of the skin and subcutaneous tissue (L00-L99).
When is it used?
- May be used when a clinician documents lichen planopilaris in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
- This entry may represent a broader category rather than the most specific billable code.
Code hierarchy
chapter
12Diseases of the skin and subcutaneous tissue (L00-L99)
block
L60-L75Disorders of skin appendages
category
L66Cicatricial alopecia [scarring hair loss]
currentL66
Where you may see this code
You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.
Related specialists
Dermatologist
Related codes
Sibling codes
Mapped diagnoses and classifications
SNOMED_CT 717055000high
Frontal fibrosing alopecia
Source: SNOMED International ICD-10 map
SNOMED_CT 718215008high
Graham Little Piccardi Lassueur syndrome
Source: SNOMED International ICD-10 map
SNOMED_CT 64540004high
Lichen planopilaris
Source: SNOMED International ICD-10 map
SNOMED_CT 721180007high
Lichen planopilaris of vulva
Source: SNOMED International ICD-10 map
SNOMED_CT 402350005high
Scarring alopecia due to lichen planus of scalp
Source: SNOMED International ICD-10 map
Coding guidelines
Compatibility
Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.
Legacy codes
L66.1
Replacement codes
L66.10 — Lichen planopilaris, unspecifiedL66.11 — Classic lichen planopilarisL66.12 — Frontal fibrosing alopeciaL66.19 — Other lichen planopilaris
Common synonyms
Lichen planopilaris
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.