Drugs involved: primarily phenytoin, carbamazepine, phenobarbital
Very common clinical findings (affect 90+ percent):
(1) fever (38 to 40°C, may be spiking) with negative blood, urine and CSF cultures
(2) skin rash (patchy macular erythema, maculopapular, erythroderma, exfolliative dermatitis; often pruritic)
Common clinical findings (affect 50-70%)
(1) lymphadenopathy with biopsy showing benign lymphoid hyperplasia or pseudolymphoma
(2) hepatitis (with or without hepatosplenomegaly)
(3) multi-organ involvement (combinations of cardiac, gastrointestinal, CNS, pulmonary, renal)
(4) hematologic abnormality (eosinophilia, atypical lymphocytosis, Coombs-negative hemolytic anemia, thrombocytopenia, neutrophilia or neutropenia)
Occasional clinical findings (10-25%):
(1) facial or periorbital edema
(2) myalgia and/or arthralgias
(3) interstitial nephritis
(4) pharyngitis
Infrequent clinical findings:
(1) anorexia
(2) carditis
(3) conjunctivitis
(4) encephalitis
(5) myositis and/or rhabdomyolysis
(6) pneumonitis
(7) lymphocytic thyroiditis
(8) mucositis
Confirmation of diagnosis:
(1) exclusion of other causes (infection, autoimmune, toxic)
(2) recurrence of symptoms on re-exposure (because of the risks entailed, this often is not performed)
