Grapefruit and prescription meds, when are they safe to mix?

Doctors advise patients who take statin drugs and some other medication to refrain from drinking grapefruit juice or eating the fruit. What are the risks?

Grapefruit juice is a problem when consumed by people who take a long list of medication, not just statins.

In California, Florida and other states with grapefruit trees that dot the landscape, heading outside to pick a fresh piece of fruit to eat is common. Unfortunately, there can be a price paid for the simple act of doing so and particularly if you take a statin drug.

A statin is a class of prescription medication that treats patients with high cholesterol. They are sold under brand names, including Lipitor as well as generic off-patent formulas.

The grapefruit-statin connection is widely known, yet each year patients show up at physicians' offices complaining of terrible side effects after mixing the two. Some people just ignore warning labels or make decisions that run counter to the advice of their physicians, wondering what could be so harmful as to interfere with their love of grapefruits.

Common side effects are diarrhea, upset stomach, muscle and joint pain, and changes in some blood tests, but there are more serious effects.

Pfizer, the company that introduced Lipitor warns customers about:

Muscle weakness or pain that is out of the ordinary
Liver problems that are evidenced by fatigue, loss of appetite, upper belly pain, dark colored urine or yellowing of the skin or whites of the eyes.

Physicians are advised to take blood tests of statin patients prior to prescribing the drug and during treatment to check for liver damage.

Why all the fuss?

The U.S. Food and Drug Administration (FDA) has provided this explanation:

"The juice increases the absorption of the drug into the bloodstream. When there is a higher concentration of a drug, you tend to have more adverse events.” Those would be the side effects listed for the medication.

Does it mean that fans of grapefruits and juice must say goodbye forever? The answer is no.

Although it is best to be safe, doctors may tell patients that cautious consumption is advised. In the words of the FDA, "Drinking grapefruit juice several hours before or several hours after you take your medicine may still be dangerous."

The caution flag is out for the "several hours" time frame, but physicians will tell patients that if they take their statins at night, as is recommended, an early morning dose of the fruit or its juice should be tolerable without problems.

As is always the case with these kinds of situation, advising your doctor of your behavior is always the best way to proceed.

What other prescription meds are on the "do not mix with grapefruits" list? Once again we turn to the FDA:

  • some blood pressure-lowering drugs, such as Nifediac and Afeditab (both nifedipine)
  • some organ transplant rejection drugs, such as Sandimmune and Neoral (both cyclosporine)
  • some anti-anxiety drugs, such as BuSpar (buspirone)
  • some anti-arrhythmia drugs, such as Cordarone and Nexterone (both amiodarone)
  • some antihistamines, such as Allegra (fexofenadine)

The above list is not exhaustive. Some patients will not manifest the side effects listed above. Check with your own physician.

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