How Does Grapefruit Seed Extract Interact With Statin Drugs?

Grapefruit seed extract is thought to be a way to lower blood pressure naturally. It can interact with cholesterol-fighting statin drugs by increasing the amounts of those medications in the bloodstream. Some recent studies show that grapefruit seed extract may actually interfere with the body's ability to absorb some blood pressure medications. And that is the key to a potentially dangerous interaction, as demonstrated in evidence gathered from studying interactions between statins and grapefruit juice.

Specific statin interaction

Not all statins are affected by grapefruit juice. Statins found to be adversely affected by consumption of grapefruit juice are:
• atorvastatin (Lipitor)
• lovastatin (Mevacor)
• simvastatin (Zocor)

Statins that do not demonstrate the same interaction issues to those drugs listed above are:
• rosuvastatin (Crestor)
• pravastatin (Pravachol)
• fluvastatin (Lescol)

According to some scientists, this could be because those statins aren't broken down by the same enzymes.

How Much?

Several studies show it takes only one glass of juice to produce the effect of an accumulation of statins in the body. One whole grapefruit can produce the same interaction. While rosuvastatin, pravastatin and fluvastatin have been shown to not have as dramatic an interaction, it is recommended that patients avoid grapefruit products while taking these medications.

Moderation

Mayo Clinic cardiologist Dr. Gerald Gau concurs that the consumption of grapefruit juice was shown to have the effect of increasing the dosage of statins, but in the Mayo studies the participants consumed an entire quart of grapefruit juice at the same time the statin was taken when this effect was produced. According to Dr. Gau, if a patient eats a half a grapefruit in the morning then takes the prescribed dosage of statin at night, no interactions should occur. His recommendation is to simply not combine the two and be aware that if you do, you will be increasing your dosage of statin.

Statin Side Effects

Myalgia is a common side effect of taking statins. Myalgia is a chronic muscle pain that can occur when the dosage of statins is too high for the patient's tolerance. This is a condition that could result from consuming grapefruit juice at the same time as taking statins, and this is why some doctors recommend their patients don't consume grapefruit products at the same time they're taking a dose of statin. Typically, if myalgia occurs from statin usage, it is recommended that the patient refrain from taking the statin immediately, then call their doctor. Myalgia symptoms usually subside in a week to 10 days once the patient stops taking them.

The compound bergamottin is found in grapefruit, and when it interacts with certain enzyme systems in the body, it can prevent these enzymes from breaking down statins, which causes the drug to accumulate in high levels in the body. Some of the conditions this can cause are liver damage and rhabdomyolysis (severe muscle and kidney damage).