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xMenace

Grapefruit Juice Can Interact With Medicines!

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xMenace

Apparently most people don't know this.

 

Grapefruit Juice Can Interact With Medicines! - Mens Health: Health and Medical Information About Mens Health Issues on MedicineNet.com

 

Grapefruit Juice Can Interact HBP Medicines!

Original Medical Author: William C. Shiel, Jr, MD, FACP, FACR

Medical Editor: Jay W. Marks, MD

 

A nutraceutical is a food or part of a food that allegedly provides medicinal or health benefits, including the prevention and treatment of disease. Grapefruit juice has been touted as containing many compounds that can reduce hardening of the arteries (atherosclerosis) and even the risk of cancer. Grapefruit juice can, therefore, be justifiably referred to as a classic nutraceutical. However, for many persons taking certain medications, grapefruit juice might actually better be termed a "nutrapollutical!"

 

It turns out that grapefruit juice can directly or indirectly interact in important ways with a number of medications. This is especially important since grapefruit juice is consumed by approximately one fifth of Americans for breakfast - a time of the day when medications also are commonly taken.

 

Grapefruit juice blocks special enzymes in the wall of the small intestine that actually destroys many medications and prevents their absorption into the body. Thus, smaller amounts of the drugs get into the body than are ingested. When the action of this enzyme is blocked, more of the drugs get into the body and the blood levels of these medications increase. This can lead to toxic side effects from the medications.

 

Amazingly, this remarkable food-drug interaction was discovered completely by accident over a decade ago! Researchers were investigating whether alcohol could interact with felodipine (Plendil) and used a solution of alcohol with grapefruit juice to mask the taste of alcohol for the study. Researchers discovered that blood levels of felodipine were increased several fold more than in previous studies. This increased blood level caused an increase in the effect and side effects of felodipine. Further research revealed that the grapefruit juice itself was actually increasing the amount of the study drug in the body.

 

Research about the interaction of grapefruit juice with drugs suggests that compounds in grapefruit juice, called furanocoumarins (e.g. bergamottin), may be responsible for the effects of grapefruit juice. Researchers believe that furanocoumarins block the enzymes in the intestines that normally break down many drugs. One glass of grapefruit juice could elicit the maximum blocking effect, and the effect may persist for longer than 24 hours. Since the effects can last for such a prolonged period of time, grapefruit juice does not have to be taken at the same time as the medication in order for the interaction to occur. Therefore, unlike similar interactions, where the interaction can be avoided by separating the administration of the two interacting agents by a couple of hours, administration of grapefruit juice with susceptible drugs should be separated by 24 or more hours to avoid the interaction. Since this is not practical for individuals who are taking a medication daily, they should not consume grapefruit juice when taking medications that are affected by grapefruit juice.

 

The grapefruit juice-drug interaction can lead to unpredictable and hazardous levels of certain important drugs.

 

These are medications with which grapefruit juice should NOT be consumed unless advised by a doctor:

 

Statins (Cholesterol Drugs): lovastatin (Mevacor), atorvastatin Lipitor, Simvastatin Zocor, simvastatin/ezetimibe Vytorin

Antihistamines: Ebastine, Seldane (terfenadine, taken off the U.S. market)

Calcium Channel Blockers (Blood Pressure Drugs): nimodipine (Nimotop), Felodipine (Nitrendipine, Plendil), Pranidipine, nisoldipine (Sular), nicardipine (Cardene), verapamil (Verelan)

Psychiatric Medications: buspirone (Buspar), triazolam (Halcion), carbamazepine (Tegretol), diazepam (Valium), midazolam (Versed), sertraline (Zoloft)

Intestinal Medications: cisapride, taken off the U.S. market (Propulsid)

Immune Suppressants: cyclosporine (Neoral), (tacrolimus) Prograf

Pain Medications: Methadone

Impotence Drug (erectile dysfunction): sildenafil (Viagra)

Ant-HIV medication : saquinavir (Invirase)

Antiarrhythmics: amiodarone (Cordarone)

Toxic blood levels of these medications can occur when patients taking them consume grapefruit juice. The high blood levels of the medications can cause damage to organs or impair the organs normal function, which can be dangerous. If you or a family member are taking any of these medications, beware of the "nutrapollutical" grapefruit juice.

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brendersue

I just read a report two days ago that said apple juice and orange juice can have the opposite effect on many meds - making them LESS effective. My mother takes Neoral and drinks orange juice every morning for breakfast. As long as she drinks the same amount of juice every day, I guess her levels are going to be OK. I told her not to quit the orange juice without letting her Dr know.

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beau91

John,thanks for the information.on my prescripton of Glucophage (metformin) It does say :do not take Grapefruit juice .But they don't always put the information on your pills bottles Bye Ricky

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Cassini

Thanks for the info, John.

 

I haven't been able to eat a grapefruit in years, or my favourite, a big cold glass of Ruby Red in the morning. I take quite a cocktail of meds for different things but all of mine are marked.

 

Armed with this additional info, it was interesting to see how this actually works in the body.

 

Thanks again,

Helen

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davef

John,

 

Thanks for that. Just passed it along to my Dad who drinks graprefruit juice from time to time and is in Statins and come cardic meds. I never really cared for gf juice and since being DX'ed I only drink OJ if low.

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Eddy

Thanks for that find. I knew that grapefruit juice amplified many medications, but didn't know the mechanism -- or that it could be so dangerous.

 

Wow. Thanks again!

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Eddy
I just read a report two days ago that said apple juice and orange juice can have the opposite effect on many meds - making them LESS effective.

 

Now we just need to find the optimum blend of orange and grapefruit! ;)

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