2026 ICD-10-CM Diagnosis Code L43Lichen planus

ICD-10-CM Codes›L00–L99›L40-L45›L43

ICD-10-CM L43
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L43 is a non-billable ICD-10-CM category code for lichen planus, so it cannot be submitted on claims. Use a more specific code from this category instead, such as L43.0, L43.1, L43.2, and L43.3.

Code Identity

ICD-10-CM Code
L43
Billable Status
No — Non-Billable Category
Code Describes
Lichen planus
Chapter
L40-L45
Papulosquamous disorders

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL40-L45Papulosquamous disorders
CategoryL43Lichen planus
This CodeL43Lichen planus

Specific Coding for Lichen planusOverview

Non-specific codes like L43 require more characters. Use one of these billable codes instead:

  • Use L43.0 for Hypertrophic lichen planus

  • Use L43.1 for Bullous lichen planus

  • Use L43.2 for Lichenoid drug reaction

  • Use L43.3 for Subacute (active) lichen planus

  • Use L43.8 for Other lichen planus

  • Use L43.9 for Lichen planus, unspecified

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Type 1 Excludes

  • lichen planopilaris L66.1

Clinical InformationClinical

  • Lichen Planus

    an inflammatory, pruritic disease of the skin and mucous membranes, which can be either generalized or localized. it is characterized by distinctive purplish, flat-topped papules having a predilection for the trunk and flexor surfaces. the lesions may be discrete or coalesce to form plaques. histologically, there is a saw-tooth pattern of epidermal hyperplasia and vacuolar alteration of the basal layer of the epidermis along with an intense upper dermal inflammatory infiltrate composed predominantly of t-cells. etiology is unknown.

  • Lichen Planus, Oral

    oral lesions accompanying cutaneous lichen planus or often occurring alone. the buccal mucosa, lips, gingivae, floor of the mouth, and palate are usually affected (in a descending order of frequency). typically, oral lesions consist of radiating white or gray, velvety, threadlike lines, arranged in a reticular pattern, at the intersection of which there may be minute, white, elevated dots or streaks (wickham's striae). (jablonski, illustrated dictionary of dentistry)

  • Atrophic Lichen Planus

    a rare form of lichen planus that is characterized by well-demarcated, white-bluish papules or plaques with central atrophy.

  • Bullous Lichen Planus

    a rare form of lichen planus that is characterized by the formation of vesico-bullous lesions on top of preexisting lichen planus papules or on normal skin.

  • Hypertrophic Lichen Planus

    a form of lichen planus that is characterized by plaques of markedly thickened skin that is often extremely pruritic and localized to the lower legs. it can result in permanent pigmentation and scarring.

  • Lichen Planus

    a chronic, recurrent, pruritic inflammatory disorder of unknown etiology that affects the skin and mucus membranes. it presents with rashes and papules that tend to resolve spontaneously. it may be associated with hepatitis c. certain drugs that contain arsenic or bismuth are associated with reactions mimicking lichen planus.

  • Lichen Planus-Like Keratosis|Lichenoid Keratosis

    a benign intraepidermal squamoproliferative neoplasm characterized by irregular acanthosis, hyperkeratosis, parakeratosis, and prominent chronic inflammation.

  • Lichenoid Drug Eruption|Drug-induced Lichen Planus|Drug-induced Lichen Planus

    a red or violaceous flat-topped, papular eruption that is induced by exposure to a variety of medications or environmental agents.

  • Oral Lichen Planus

    a chronic, autoimmune inflammatory condition of the mucous membranes in the oral cavity that affects approximately two percent of the population and is most often seen in middle aged women. it is characterized by white, lacy patches; red, swollen tissue; papules and plaques; or open sores. the lesions are typically bilateral.

Patient EducationClinical

Skin Conditions

Your skin is your body's largest organ. It covers the entire outside of your body. There are many ways that your skin protects your body and helps keep you healthy. For example, it:

The full article covers:

  • What does your skin do?
  • What problems and conditions can affect your skin?
  • How can I keep my skin healthy?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About L43Overview

Is L43 (Lichen planus) a billable code?

No. This is a category header that groups the codes for lichen planus, and headers cannot be submitted on claims. Claims for lichen planus need a more specific code from this category, such as L43.0, L43.1, and L43.2.