RECURRENT FIXED DRUG ERUPTION CAUSED BY CITIOLONE

Citiolone (N-acetylhomocysteinethiolactone) is a thiolic-derived medic ation frequently used in Spain and in other countries as a mucolytic a gent for the treatment of certain hepatic disorders. Mucolytic drugs h ave rarely been implicated in the fixed drug eruption etiology. We rep ort on a patient who presented several episodes of fixed exanthema rel ated to citiolone intake. The patch test with citiolone (10% in dimeth yl sulfoxide) was negative. The diagnosis was confirmed by a positive controlled oral challenge test. Other mucolytic thiolic-derivatives (N -acetylcysteine) were tolerated by the patient, thus crossreactivity b etween these drugs seems to be unlikely.