2027 ICD-10-CM Diagnosis Code L43.3Subacute (active) lichen planus

ICD-10-CM Codes›L00–L99›L40-L45›L43

ICD-10-CM L43.3
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

L43.3 is a billable ICD-10-CM diagnosis code for subacute (active) lichen planus. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 606 through 607. Coders also document this condition as subacute active lichen planus. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified inflammatory condition of skin.

Code Identity

ICD-10-CM Code
L43.3
Billable Status
Yes — Valid for Submission
Code Describes
Subacute (active) lichen planus
Short Description
Subacute (active) lichen planus
Same as the full description in the CMS dataset.
Parent Code
L43
Lichen planus

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL40-L45Papulosquamous disorders
CategoryL43Lichen planus
This CodeL43.3Subacute (active) lichen planus

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Subacute active lichen planus

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to L43.3: its own notes plus those printed at L43 and Chapter 12. A note printed at a category, block or chapter applies to every code under it.

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Lichen planus tropicus

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From L43 Lichen planus applies to 6 codes

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 12 (L00-L99) Diseases of the skin and subcutaneous tissue applies to 1,001 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • lipomelanotic reticulosis (I89.8)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • systemic connective tissue disorders (M30-M36)
  • viral warts (B07.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR SKN002
Other specified inflammatory condition of skin
Default principal diagnosis: inpatient Yes · outpatient Yes

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.

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.

Convert L43.3 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
697.0 Lichen planus
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About L43.3Overview

What is the ICD-10 code for subacute (active) lichen planus?

The ICD-10-CM code for subacute (active) lichen planus is L43.3 (sometimes written as L433). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is L43.3 (Lichen planus) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report subacute (active) lichen planus on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does L43.3 group to?

When subacute (active) lichen planus is the principal diagnosis on an inpatient stay, it groups to MS-DRG 607, 606, with relative weights from 0.8772 to 1.5721 depending on complications. Higher weights mean higher Medicare reimbursement.

Can L43.3 be reported with a code from L66.1?

Not as a rule. The Excludes1 note at L43, which applies to L43.3, lists "lichen planopilaris (L66.1-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What is the ICD-9 equivalent of L43.3?

Under the General Equivalence Mappings, subacute (active) lichen planus converts to ICD-9-CM 697.0 (lichen planus). The mapping is approximate, so confirm the match fits the documentation.