Phenytoin, fosphenytoin associated with serious skin reactions in patient subset

FDA informed healthcare professionals that the agency is evaluating data regarding a potentially increased risk of serious skin reactions, including Stevens Johnson syndrome and toxic epidermal necrolysis, in association with phenytoin (Dilantin, Pfizer; Phenytek, Mylan; generic phenytoin) or fosphenytoin (Cerebyx, Pfizer; generic fosphenytoin) treatment in Asian patients who are positive for the human leukocyte antigen allele HLA-B*1502.

FDA informed healthcare professionals that the agency is evaluating data regarding a potentially increased risk of serious skin reactions, including Stevens Johnson syndrome and toxic epidermal necrolysis, in association with phenytoin (Dilantin, Pfizer; Phenytek, Mylan; generic phenytoin) or fosphenytoin (Cerebyx, Pfizer; generic fosphenytoin) treatment in Asian patients who are positive for the human leukocyte antigen allele HLA-B*1502.

An increased risk of Stevens Johnons syndrome and toxic epidermal necrolysis has been noted previously in association with carbamazepine, an antiepileptic drug that is structurally similar to phenytoin.

FDA has recommended that healthcare professionals should weigh the potential risks and benefits associated with phenytoin or fosphenytoin treatment before initiating therapy.