Symmetrical drug-related intertriginous and flexural exanthema caused by valacyclovir.

Drug-related eruptions that appear only on intertriginous or flexural folds and in gluteal areas have recently been termed symmetrical drug-related intertriginous and flexural exanthema (SDRIFE). We report a case of a 56-year-old woman with acute erythematous rash in the intertriginous areas after treatment with the L-valine ester of acyclovir, valacyclovir. Oral-challenge tests resulted in erythematous pruritic rash in the intertriginous area by valacyclovir. The patient was diagnosed as having SDRIFE due to valacyclovir.