Urticaria and erythema (L49-L54)
ICD-10 codes L49-L54 classify various skin conditions characterized primarily by urticaria (hives) and erythema (redness), including exfoliation due to red skin inflammation, allergic and non-allergic urticaria types, erythema multiforme and its severe forms like Stevens-Johnson syndrome, as well as other distinct erythematous skin disorders.
This code range details exfoliation related to the extent of erythema coverage on the body (L49 series), as well as multiple forms of urticaria (L50), such as allergic (including occupational or food-induced urticaria), idiopathic, cold and heat induced, dermatographic, cholinergic, and contact urticaria. Common synonyms like "contact urticaria" and "allergic urticaria" correspond with L50.0 and L50.6. The range also captures erythema multiforme (L51) with its variants including nonbullous, Stevens-Johnson syndrome, and toxic epidermal necrolysis, all serious immune-related skin reactions. L52 refers to erythema nodosum, an inflammatory condition often linked with infections or drug reactions. Other erythematous conditions (L53) cover diverse drug-induced, infectious, or idiopathic red skin disorders, while L54 includes erythema occurring as part of other systemic diseases. These codes are essential for categorizing inflammatory skin diseases presenting with redness and wheals, aiding in precise documentation and management.
Diseases of the skin and subcutaneous tissue (L00–L99)
Urticaria and erythema (L49-L54)
L49 Exfoliation due to erythematous conditions according to extent of body surface involved
- L49.0 Exfoliation due to erythematous condition involving less than 10 percent of body surface
- L49.1 Exfoliation due to erythematous condition involving 10-19 percent of body surface
- L49.2 Exfoliation due to erythematous condition involving 20-29 percent of body surface
- L49.3 Exfoliation due to erythematous condition involving 30-39 percent of body surface
- L49.4 Exfoliation due to erythematous condition involving 40-49 percent of body surface
- L49.5 Exfoliation due to erythematous condition involving 50-59 percent of body surface
- L49.6 Exfoliation due to erythematous condition involving 60-69 percent of body surface
- L49.7 Exfoliation due to erythematous condition involving 70-79 percent of body surface
- L49.8 Exfoliation due to erythematous condition involving 80-89 percent of body surface
- L49.9 Exfoliation due to erythematous condition involving 90 or more percent of body surface
Exfoliation due to erythematous conditions according to extent of body surface involved (L49)
L51 Erythema multiforme
- L51.0 Nonbullous erythema multiforme
- L51.1 Stevens-Johnson syndrome
- L51.2 Toxic epidermal necrolysis [Lyell]
- L51.3 Stevens-Johnson syndrome-toxic epidermal necrolysis overlap syndrome
- L51.8 Other erythema multiforme
- L51.9 Erythema multiforme, unspecified
Erythema multiforme (L51)
- L52 Erythema nodosum
Erythema nodosum (L52)
- L54 Erythema in diseases classified elsewhere
Erythema in diseases classified elsewhere (L54)
Instructional Notations
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.
