ICD-10 Code L51.1 – Stevens-Johnson syndrome (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L51.1 – Stevens-Johnson syndrome
What it is
Stevens-Johnson syndrome is a severe mucocutaneous reaction with skin and mucosal involvement. It is usually classified as a serious drug- or infection-related hypersensitivity condition.
Clinical signs
Typical findings include painful rash, blistering, and skin detachment with mucosal lesions. Clinical features vary; refer to documentation, especially when distinguishing it from toxic epidermal necrolysis.
When to use this code
Use L51.1 when the provider documents Stevens-Johnson syndrome by name. It is appropriate when the record supports acute mucocutaneous involvement and the diagnosis is not documented as toxic epidermal necrolysis or another erythema multiforme variant.
Do not use for
Do not use this code for simple drug rash, erythema multiforme minor, or unspecified adverse skin reactions. Check documentation if the note only says “rash” or “allergic reaction.”
Coding tip
Code the diagnosis exactly as documented and query if the record does not clearly distinguish Stevens-Johnson syndrome from toxic epidermal necrolysis.