It's better to be safe than sorry pusskin, Here's why you can't take simvasstatin with grapefruit juice in case you were wondering.
Grapefruit contains the compound bergamottin, which interacts with certain enzyme systems in the body, such as cytochrome P-450 and P-glycoprotein. These enzyme systems are responsible for breaking down statins, as well as other drugs, into more usable chemicals and transporting them in the body.
When grapefruit juice is consumed at or around the time you take your statin, the components in grapefruit prevent these enzyme systems from breaking down the drug, causing the drug to accumulate in high amounts in the body. This can be very dangerous and can cause a variety of health problems, such as liver damage or a rare condition called rhabdomyolysis (severe muscle and kidney damage).