Pravastatin and Grapefruit
Usually, consuming grapefruit products such as grapefruit juice and grapefruit supplement along while taking lipid-lowering statins is contraindicated. However, clinical studies reveal that unlike other statins, pravastatin is not significantly affected by grapefruit juice.
Hence, people taking pravastatin (Pravachol) can generally continue enjoying grapefruit while taking this medication.
If your physician has prescribed you with a different statin including, but not limited to, atorvastatin (Lipitor), lovastatin (Altoprev, Mevacor) and simvastatin (Zocor), you need to avoid consuming large amounts of grapefruit juice. However, if you feel that you cannot forbid yourself from taking this tangy yet sweet fruit, you can discuss with your physician the possibility of switching your medication to pravastatin. Again, do not change your medication without consulting your physician.
Why is grapefruit contraindicated for patients taking statins other than pravastatin?
Grapefruit is notorious for its potential interaction with different medications. It contains a certain compound which inhibits action of enzymes (specifically cytochromes) necessary for the metabolism of some drugs, statins being one of the well known. Normally, these enzymes are abundant in the liver although some of them are located in other parts of the body such as in the gastrointestinal tract. One of these cytochromes, CYP3A4, is concentrated in the small intestine. This specific cytochrome is essential in the first-pass metabolism of statins. However, grapefruit can significantly inhibit the activity of this intestinal cytochrome leading to an increased level of statin in the blood. This can eventually cause drug toxicity and serious side effects such as liver damage and muscle injury.
Clinical studies suggest that even as little as 8 oz. of grapefruit can cause substantial increase in the drug levels. In addition, the effect of consuming one serving of grapefruit can last for an entire 24 hours. This means that even if you take the statin several hours after drinking grapefruit, drug interaction is still possible.
Why Grapefruit Use is ok with Pravastatin?
Clinical studies conducted on pravastatin suggest that grapefruit juice does not have a direct effect on the metabolism of this medication. Unlike other statins that rely on the CYP3A4 mediated metabolism, pravastatin is not significantly affected by this intestinal cytochrome. Basically, this medication follows a different metabolic pathway. This means that even if you consume grapefruit while taking pravastatin, serious side effects are unlikely to happen.
Take note, however, that not all patients react the same way to medications. In some cases, your physician may recommend avoiding grapefruit while on pravastatin to prevent potential problems. It may also be possible that grapefruit is avoided due to other underlying medical conditions or other medications taken in addition to pravastatin. It is best to discuss with your physician possible grapefruit juice restrictions.