Excludes1 pair
L24- vs L30.9
L24 and L30.9 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on L24
dermatitis NOS (L30.9)
L24
Irritant contact dermatitis
Not billable
- Chapter 12
- Diseases of the skin and subcutaneous tissue
- Section
- L20-L30
L30.9
Dermatitis, unspecified
BillableUnspecified
- Chapter 12
- Diseases of the skin and subcutaneous tissue
- Section
- L20-L30
Use when the record says
- Eczema NOS
Indexed under
- Dermatitis (eczematous)
- Eczema (acute) (chronic) (erythematous) (fissum) (rubrum) (squamous)
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