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L23

Non-Billable (Header)

Allergic contact dermatitis

Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)

What This Code Means

L23 is the ICD-10-CM diagnosis code for allergic contact dermatitis. L23 sits in the ICD-10-CM chapter for diseases of the skin and subcutaneous tissue (l00-l99), within the section covering dermatitis and eczema (l20-l30).

Header codes like L23 cannot be reported on claims directly — they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at L23's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for L23 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Excludes 1 — Do NOT code together

Excludes 2 — Not included here, may code separately

  • dermatitis due to substances taken internally (L27.-)
  • dermatitis of eyelid (H01.1-)
  • diaper dermatitis (L22)
  • eczema of external ear (H60.5-)
  • irritant contact dermatitis (L24.-)
  • perioral dermatitis (L71.0)
  • radiation-related disorders of the skin and subcutaneous tissue (L55-L59)

Child Codes

Code Hierarchy

L23Allergic contact dermatitis
L23Allergic contact dermatitis

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