Erythema multiforme (L51) ICD-10-CM
The L51 code range covers erythema multiforme with 7 ICD-10-CM diagnosis codes. 6 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
- code for adverse effect, if applicable, to identify drug T36 T50
- code to identify associated manifestations, such as:
- arthropathy associated with dermatological disorders M14.8
- conjunctival edema H11.42
- conjunctivitis H10.22
- corneal scars and opacities H17
- corneal ulcer H16.0
- edema of eyelid H02.84
- inflammation of eyelid H01.8
- keratoconjunctivitis sicca H16.22
- mechanical lagophthalmos H02.22
- stomatitis K12
- symblepharon H11.23
- code to identify percentage of skin exfoliation L49
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Codes in the L51 Range 7 codes · 6 billable
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the L51 range.
Erythema Multiforme
A skin and mucous membrane disease characterized by an eruption of macules, papules, nodules, vesicles, and/or bullae with characteristic bull's-eye lesions usually occurring on the dorsal aspect of the hands and forearms.
About the L51 Code Range
ICD-10 code L51 covers erythema multiforme, a skin condition characterized by target-like lesions and inflammation. This coding section includes specific subtypes such as nonbullous erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, and related overlap syndromes.
The codes within L51 are used to classify various forms of erythema multiforme and related severe skin reactions. For example, L51.0 represents nonbullous erythema multiforme, sometimes called non-bullous erythema multiforme, which involves skin inflammation without blistering. L51.1 stands for Stevens-Johnson syndrome (SJS), a serious condition involving mucous membrane damage and skin detachment, often drug-induced or related to infections. The closely related L51.2 refers to toxic epidermal necrolysis (Lyell syndrome), a more extensive form of skin detachment. Overlap of these two conditions is coded as L51.3. Other specified forms and unspecified cases are coded under L51.8 and L51.9, which include various clinical presentations such as erythema multiforme caused by infections, drugs, or unknown sources. Understanding these codes helps healthcare professionals accurately document and manage these inflammatory and allergic skin disorders.
Questions About This Page
How many billable codes are in the L51 range?
Of the 7 codes in this range, 6 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the L51 range classify?
The range classifies erythema multiforme. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
