Grapefruit juice and drug interactions

[Guest guest]

This is good to know; I thought that as long as one took

them at least 2 or 3 hours apart, that it was okay.

I do take the anti-seizure medication below and haven't noticed any

problems. I would like to understand why if one took them far apart, how it

could

still effect the drug. After all, it only takes about half to 1 hour for food

to go through one's digestive system - at least, that was my understanding. Can

anyone explain this?

blessings

Shan

 

Grapefruit juice and drug interactions

http://www.mayoclinic.com/health/food-and-nutrition/AN00413

 

I thought grapefruit juice was good for me. But now I hear that it might

interfere with my medications. Can you explain this?

- Albert / Texas

 

Answer

Grapefruit juice provides many nutrients such as vitamin C and the

antioxidant lycopene. But chemicals in grapefruit interfere with enzymes that

break down

certain drugs in your digestive system. This can result in abnormally high

blood levels of these drugs and an increased risk of serious side effects.

 

The exact chemical or chemicals in grapefruit juice that cause this

interaction aren't known. But they're present in the pulp and peel of grapefruit

as

well as in the juice. For this reason, any grapefruit product — including

dietary

supplements that contain grapefruit bioflavonoids — can interact with some

medications. You may also want to avoid tangelos, a hybrid grapefruit. They may

have a similar effect.

 

Grapefruit and drug interactions

The following drugs are known to have potentially serious interactions with

grapefruit products

 

Type of drug Names of drugs

 

Anti-seizure medications Carbamazepine (Carbatrol, Tegretol)

 

Antidepressants or psychiatric medications Buspirone (BuSpar), clomipramine

(Anafranil) and sertraline (Zoloft)

 

Benzodiazepines Diazepam (Valium), triazolam (Halcion)

 

Calcium channel blockers Felodipine (Plendil), nifedipine (Adalat,

Procardia), nimodipine (Nimotop), nisoldipine (Sular) and possibly verapamil

(Isoptin, Verelan)

 

Human immunodeficiency virus (HIV) protease inhibitors Saquinavir

(Fortovase, Invirase) and indinavir (Crixivan)

 

HMG-CoA reductase inhibitors Simvastatin (Zocor), lovastatin (Mevacor) and

atorvastatin (Lipitor), simvastatin-ezetimibe (Vytorin)

 

Immunosuppressant drugs Cyclosporine (Neoral, Sandimmune), tacrolimus

(Prograf) and sirolimus (Rapamune)

 

Anti-arrhythmic drugs Amiodarone (Cordarone)

 

Pain medications Methadone

 

Impotence drug Sildenafil (Viagra)

 

If you take any of these drugs, you should avoid grapefruit products, unless

otherwise directed by your doctor. Waiting to take these medications even up

to 24 hours after you drink grapefruit juice will not prevent an interaction.