ICD-10 Code L43.3 – Subacute (active) lichen planus (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L43.3 – Subacute (active) lichen planus
What it is
L43.3 identifies subacute, active lichen planus, an inflammatory skin condition. You use it when documentation specifically states this active or subacute form.
Clinical signs
Typical findings include pruritic, violaceous, flat-topped papules or plaques, often with a polygonal shape. Oral or other mucosal involvement may occur; clinical features vary, so refer to documentation.
When to use this code
Use L43.3 when the provider documents subacute or active lichen planus without a more specific site or subtype. It may apply to skin or mucosal disease when the record clearly supports that diagnosis. Check documentation if the note only says “lichen planus.”
Do not use for
Do not use this code for lichen planus variants that are separately specified elsewhere, or for nonspecific rash without a confirmed diagnosis. Check documentation if the term “active” is not clearly linked to lichen planus.
Coding tip
Code the condition only when the clinician explicitly documents subacute or active lichen planus.