Drug rash with eosinophilia and systemic symptoms syndrome

This code represents a severe, idiosyncratic drug reaction characterized by a widespread skin eruption, fever, lymphadenopathy, and internal organ involvement (e.g., hepatitis, nephritis, pneumonitis). It is a delayed hypersensitivity reaction that typically manifests 2-8 weeks after drug initiation. The syndrome is also known as DRESS (Drug Reaction with Eosinophilia and Systemic Symptoms).

Use this code when documentation clearly indicates a diagnosis of DRESS syndrome, often triggered by anticonvulsants, allopurinol, or sulfonamides. Supporting documentation should detail the systemic symptoms, eosinophilia, and the suspected drug culprit. This code is appropriate for both initial diagnosis and subsequent encounters related to the management of DRESS.

• Always sequence this code as the primary diagnosis when DRESS is the reason for the encounter.
• Code the specific adverse effect of the drug (e.g., T36-T50 with a 5th or 6th character of 5 for adverse effect in therapeutic use) as an additional diagnosis.
• Ensure the medical record explicitly states "DRESS syndrome" or "Drug rash with eosinophilia and systemic symptoms" to avoid confusion with other drug eruptions.