Epidemiology

Etiology

• Common triggers
  • Antiepileptics: lamotrigine, phenytoin, carbamazepine
  • dapsone, sulfamethoxazole/trimethoprim; vancomycin, minocycline; sulfonamides
  • allopurinol

Pathophysiology

Delayed hypersensitivity reaction (type IV HSR) to drug metabolites

Clinical features

• Systemic symptom
  • Fever, typically high (> 38.5°C/101.3°F) and spiking
• Diffuse rash
  • Typical manifestation: generalized morbilliform pruritic rash
    • The term morbilliform refers to a rash that looks like measles.
• Signs of internal organ involvement
  • Multiorgan failure

Diagnostics

Eosinophilia, thrombocytopenia, atypical lymphocytes often present

Treatment