Large amounts of
grapefruit juice markedly increase the
plasma levels of
lovastatin (up to 12-fold) and
simvastatin (up to 9-fold).
Large increases in the
serum levels of
lovastatin and
simvastatin are potentially hazardous because elevated statin levels carry the risk of
toxicity (muscle damage and the possible development of rhabdomyolysis). As even small quantities of
grapefruit juice can significantly affect
simvastatin levels the manufacturer says that concurrent use should be avoided. No clinically significant interaction appears to occur with atorvastatin and
pravastatin.