Is Grapefruit Dangerous to Those on Certain Medications?

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I am so glad that I am not restricted on having grapefruit and grapefruit juice in my diet; my daughter, on the other hand cannot have grapefruit at all due to the medications that she takes. My daughter takes psychotropic drugs, as well as Valium routinely. Due to these medications she is not allowed to even drink one glass of grapefruit juice.

Grapefruit juice is harmless to most people, but if you are on certain medications grapefruit juice can interfere with the pathways in which drugs are metabolized. For instance, grapefruit seems to magnify the affect of Valium (diazepam) in the body. One who is on certain medications could become critically ill. The effect might be something like an actual overdose of medication in the body.

If your doctor or pharmacist as warned you not to eat grapefruit, or drink its juice be sure to follow the instructions given to you. Something else you may not think about is that supplements that contain bioflavonoid of grapefruit can be just as dangerous. Don't forget about other fruits also that have a connection with grapefruit. You might choose oranges as a substitute for grapefruit, but be careful, because tangelos are a cross between an orange and a grapefruit. Some types of bitter oranges, such as the Seville orange that is made to make orange marmalade acts the same way that grapefruit do on the metabolism of certain medications.

Most drugs a perfectly compatible with grapefruit; however here are some of the drugs that are not compatible:

Anxiety medications - Buspar, Halcion, Versed, and Xanax

Allergy medications - Allegra

Anticoagulant - Coumadin

Antidepressants - Luvox, Zoloft

Anti-seizure medication - Tegretol

OTC Cough medicine - Dextromethorphan

Prostate medication - Proscar

Sleep medication - Halcion

Asthma and respiratory medication - Theophylline

Cancer medications - Cyclophosphamide, etoposide, ifosfamide, tamoxifen, vinblastine, incrusting

Cholesterol medications - Lipitor, Lescol, Mevacor, Zocor

Drugs for hearth rhthm - Cordarone, and Quinidine

E.D. medications - Viagra, Cialis

Heart and blood pressure medications - Coreg, Cardizem, Plendil, Cardene, Adalat, Procardia, Nimotop, Sular, Covera, Calan, Verelan

In summary, grapefruit inhibits the enzyme (CYP 3A4 located in the intestinal tract) that break down the dugs in the system. Some drugs, such as BuSpar, Prozac, Tegretol and Lipitor normally break down before the drug actually enters the blood stream; however, when one has eaten grapefruit or drank its juice the medication cannot break down properly and the medication becomes much more potent and the result could be life threatening. Drugs that cannot be taken in the presence of grapefruit or its juice (not just when the medications are swallowed), can magnify to toxic levels.

Before taking any new medication, it is better to be safe and ask your doctor or pharmacist before eating grapefruit or drinking its juice. If you were to drink a glass of grapefruit juice, or eat a grapefruit every day you could be building up long lasting grapefruit effect in your body. The effects of grapefruit can last up to 48 hours in your body.