The FDA is investigating the possibility that phenytoin and fosphenytoin sodium increases the risk of serious skin reactions, such as Stevens Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), in Asian patients positive for the human leukocyte antigen (HLA) allele, HLA-B*1502. These patients include those of the Han Chinese, Filipino, Malaysian, South Asian Indian and Thai ancestry. As a result, phenytoin and fosphenytoin therapy should be avoided as alternatives to carbamazepine in these patient populations.
Phenytoin [Dilantin (from Pfizer), Phenytek (from Bertek) and generics] and fosphenytoin sodium [Cerebyx (from Pfizer) and generics] are used to control tonic-clonic (grand mal) and complex-partial seizures in epilepsy.
For more information visit www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm094919.htm.