Is L27 a billable ICD-10-CM code?

No. L27 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does L27 sit in the tabular list?

Diseases of the skin and subcutaneous tissue (L00-L99), in the block Dermatitis and eczema (L20-L30).

What cannot be coded together with L27?

L27 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

L27

L27 — Dermatitis due to substances taken internally

Non-billable headerICD-10-CM

L27 is a non-billable header ICD-10-CM code for dermatitis due to substances taken internally. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

allergy NOS (T78.40)

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

adverse food reaction, except dermatitis (T78.0-T78.1)
contact dermatitis (L23-L25)
drug photoallergic response (L56.1)
drug phototoxic response (L56.0)
urticaria (L50.-)

Other codes that can never be billed with L27

These codes carry an Excludes1 note pointing at L27. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading L27 alone.

T61Toxic effect of noxious substances eaten as seafood
T62Toxic effect of other noxious substances eaten as food
T78.4Other and unspecified allergy

Risk adjustment

L27 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead L27

5 child codes. Green means billable.

Questions about L27

Is L27 a billable ICD-10-CM code?: No. L27 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does L27 sit in the tabular list?: Diseases of the skin and subcutaneous tissue (L00-L99), in the block Dermatitis and eczema (L20-L30).
What cannot be coded together with L27?: L27 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.