L24 vs L25.9
L24 and L25.9 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on L24
contact dermatitis NOS (L25.9)
L24
Irritant contact dermatitis
Not billable
- Chapter 12
- Diseases of the skin and subcutaneous tissue
- Section
- L20-L30
L25.9
Unspecified contact dermatitis, unspecified cause
BillableUnspecified
- Chapter 12
- Diseases of the skin and subcutaneous tissue
- Section
- L20-L30
Use when the record says
- Contact dermatitis (occupational) NOS
- Contact eczema (occupational) NOS
Indexed under
- Dermatitis › contact (eczematous)
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027