L40.1 — Generalized pustular psoriasis
L40.1 is a billable, specific ICD-10-CM code for generalized pustular psoriasis. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Impetigo herpetiformis
- Von Zumbusch's disease
Other codes that can never be billed with L40.1
These codes carry an Excludes1 note pointing at L40.1. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading L40.1 alone.
Risk adjustment
L40.1 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.
Medicare coverage
L40.1 is named in 13 Medicare coverage policies — 13 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A52423Billing and Coding: Infliximab and biosimilars
- A52998Billing and Coding: Surgical Treatment of Nails
- A55639Billing and Coding: Chemotherapy Agents for Non-Oncologic Conditions
- A56416Billing and Coding: Assays for Vitamins and Metabolic Function
How L40.1 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to L40.1.
- Von Zumbusch's disease
- Impetigo›herpetiformis
- Psoriasis›pustular(generalized)
- Impetigo›herpetiformis›nonobstetrical
Related codes at this level
Codes that share L40. If L40.1 is not quite right, the correct code is usually one of these.
Questions about L40.1
- Is L40.1 a billable ICD-10-CM code?
- Yes. L40.1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does L40.1 sit in the tabular list?
- Diseases of the skin and subcutaneous tissue (L00-L99), in the block Papulosquamous disorders (L40-L45).