Fixed drug eruption: state of the art.

Fixed drug eruption (FDE) is a common type of cutaneous adverse drug reaction. There may be a genetic background as significant associations have been identified between HLA types and specific FDE.Systemic provocation is still the gold standard for establishing the offending agent in FDE,but topical provocation testing offers a promising alternative approach. A standardized method does not exist, and the approach must likely be varied for different agents. The mystery of site preference in FDE is still unresolved. Possible explanations include properties of the drug, trauma and viscerocutaneous reflex patterns.