Why is Grapefruit and Grapefruit juice is contraindicated when taking Statin Drugs

It seems to be common sense, that grapefruit and grapefruit juice would be a healthy lifestyle choice for most people. However, that is not the case for everyone. According to Caroline Levchuck and her colleagues, “A recent study at the University of California at San Francisco has shown that in some cases, grapefruit juice may actually decrease the absorption of drugs.” (Levchuck 2002) Depending on what medications a person has been prescribed, alteration in the absorption of these chemicals can be effected by the amount of grapefruit or grapefruit juice a person ingests.

According to Dr Thomas Lee, “Grapefruit juice and grapefruit itself can boost blood levels of some statins and a variety of other drugs. Something in grapefruit -- scientists aren't yet sure what -- latches onto an enzyme in the intestines called CYP3A4.” (Lee, 2006) Lee goes on to explain how this enzyme partially breaks down some drugs, knocking them out of action leading to more of the drug in the bloodstream. Statins, when they reach abnormally high levels in the blood system can damage muscles or even the liver. It appears there is a clear and present danger associated with the combined use of statin drugs and grapefruit or grapefruit juice.

The effects of grapefruit and grapefruit juice are substantial in that only small amounts can affect the body for an entire day. “One glass of grapefruit juice is enough to suppress CYP3A4 activity by half, and the effect lasts for 12-24 hours.” (Lee, 2006) There is hope, Lee mentions, “You don't have to give up grapefruit forever as long as you (and your doctor) are willing to switch to a statin or other cholesterol-lowering agent that isn't affected by grapefruit juice.” (Lee, 2006) The other alternative is to locate a better citrus drink that will not affect the body in the same way. Lee instructs patients to, “Switch to orange juice. It doesn't affect CYP3A4, and so won't boost blood levels of your statin.” (Lee, 2006)