Table 2:

Clinical features of drug hypersensitivity reactions1,7,8,10,13

ReactionClinical manifestations
Delayed drug exanthemFine macules and papules that occur days after drug initiation and resolve a few days after discontinuing the medication; lack of other systemic symptoms
IgE-mediatedCombination of urticaria, angioedema, vomiting, diarrhea, cough, wheeze, hypotension and/or syncope one to six hours after starting a medication; usually requires prior sensitization
Serum sickness-like reactionRash (usually urticarial), fever, arthralgias, lymphadenopathy one to three weeks after starting a medication; could be earlier with sensitization
SJS/TENMucosal involvement, fever, cutaneous target and bullous lesions (SJS: < 10% epidermal detachment; SJS/TEN overlap: 10%–30% epidermal detachment; TEN: > 30% epidermal detachment); possible involvement of liver, kidney, lungs
DRESSFever, eosinophilia, lymphadenopathy, liver dysfunction, possible renal dysfunction, multiple different cutaneous eruptions possible; starts up to 12 weeks after starting a medication and may persist for weeks or months after stopping the medication (Figure 1)
Allergic contact dermatitisDermatitis in area of cutaneous contact that evolves over days; requires prior sensitization (Figure 2)
Drug-induced lupus erythematosusCutaneous: photodistributed erythematous plaques
Systemic: sudden onset myalgias, fever, arthralgias, malaise several weeks after drug initiation
Fixed drug eruptionHyperpigmented plaques that recur at the same site (Figure 3)
OtherHematologic (cytopenia), hepatic (hepatitis, cholestatic jaundice), renal (interstitial nephritis), pulmonary (pneumonitis, fibrosis), vasculitis
  • Note: DRESS = drug reaction with eosinophilia and systemic symptoms, IgE = immunoglobulin E, SJS = Stevens–Johnson syndrome, TEN= toxic epidermal necrolysis.