L23.9 – Allergic contact dermatitis, unspecified cause

ICD-10-CM 2027 diagnosis code · Dermatitis and eczema

Billable code

ICD-10-CM code L23.9

Code: L23.9 (claims format: L239)
Description: Allergic contact dermatitis, unspecified cause
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 12. Diseases of the skin and subcutaneous tissue (L00-L99)
Block: L20-L30 Dermatitis and eczema
Parent codes: L23

Notes for L23.9

Applicable to:

Allergic contact eczema NOS

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

L23 – Allergic contact dermatitis

Excludes1 (not coded here):

allergy NOS (T78.40)
contact dermatitis NOS (L25.9)
dermatitis NOS (L30.9)

Excludes2 (not included here):

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)

Block L20-L30

Excludes2 (not included here):

chronic (childhood) granulomatous disease (D71-)
dermatitis gangrenosa (L08.0)
dermatitis herpetiformis (L13.0)
dry skin dermatitis (L85.3)
factitial dermatitis (L98.1)
perioral dermatitis (L71.0)
radiation-related disorders of the skin and subcutaneous tissue (L55-L59)
stasis dermatitis (I87.2)

Notes:

In this block the terms dermatitis and eczema are used synonymously and interchangeably.

Index terms for L23.9

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in L23

Frequently asked questions

What is ICD-10 code L23.9?

L23.9 is the ICD-10-CM code for allergic contact dermatitis, unspecified cause, in the block L20-L30 (Dermatitis and eczema).

Is L23.9 a billable code?

Yes. L23.9 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does L23.9 belong to?

It belongs to category L23 – Allergic contact dermatitis.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.