ICD-10 Code L43.0 – Hypertrophic lichen planus (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L43.0 – Hypertrophic lichen planus
What it is
Hypertrophic lichen planus is a chronic inflammatory skin condition marked by thickened, raised plaques. It is a specific form of lichen planus that often affects the lower legs.
Clinical signs
Look for pruritic, hyperkeratotic, violaceous or brownish plaques that may be symmetric and persistent. Clinical features vary; refer to documentation.
When to use this code
Use this code when the clinician documents hypertrophic lichen planus specifically. It also fits notes describing classic lichen planus with marked thickening or verrucous plaques, when that subtype is clearly stated.
Check documentation if the record only says “lichen planus” without subtype. Do not assume hypertrophic disease from chronic scratching alone.
Do not use for
Do not use this code for other lichen planus variants, such as oral, genital, or bullous forms, unless hypertrophic lichen planus is also documented. Check documentation for the exact subtype.
Coding tip
Code the most specific documented lichen planus subtype; if the note is nonspecific, query for clarification before assigning L43.0.