RHABDOMYOLYSIS IN PATIENTS TREATED WITH S IMVASTATIN CICLOSPORIN - ROLE OF THE HEPATIC CYTOCHROME-P450 ENZYME-SYSTEM/

We describe two patients treated with a combination of ciclosporin and simvastatin who had to be hospitalized due to rhabdomyolysis. As sugg ested by reduced ciclosporin clearance, both patients had impaired act ivity of the hepatic cytochrome P450 enzyme system, which may have con tributed to the development of rhabdomyolysis. After cessation of trea tment with simvastatin and intensive hydration, both patients recovere d within one week. While rhabdomyolysis has been described in several patients receiving the combination lovastatin/ciclosporin, so far only one case has been reported in patients treated with simvastatin/ cicl osporin. Our cases therefore suggest that this complication may be mor e frequent than previously suspected. In patients treated with ciclosp orin, HMG-CoA reductase inhibitors should be used cautiously, and conc omitant administration of drugs inhibiting the hepatic cytochrome P450 enzyme system should be avoided.