Thursday, May 9, 2013

Grapefruit Interactions with Many Drugs Should NOT be Ignored

 “DO NOT TAKE WITH GRAPEFRUIT”  This or similar grapefruit warnings on medication labels can be a common sight, but how often are these warnings actually heeded? Are you or your aging parents at risk for not heeding the warnings? You can be at serious risk.

According to a recent article in the May issue of Nursing 2013, a recent study found that there are over 85 prescription and over -the-counter medications that interact with grapefruit. Of those, 43 can have serious adverse reactions such as GI (intestinal tract) bleeding, or can be toxic to the kidneys (nephrotoxocity).


Serious Consequences
Grapefruit interactions can also have serious cardiac affects such as torsades de pointes which is a type of ventricular tachcardia (very rapid heart rate) with dangerous potential for fatal consequences. Another potential interaction can result in rhabdomyolysis which is the rapid destruction of skeletal muscles.

Only a small amount of grapefruit is required to cause these interactions. Just 2 segments of a grapefruit or one cup of grapefruit juice is sufficient to cause effects. It is important to read the labels on foods and juices or sodas as they can contain grapefruit and should be avoided. Grapefruit is a healthy and nutritious fruit, but must be avoided by those taking medications that can interact.

Actions Altered by Grapefruit
Medication actions can be significantly altered by the grapefruit by increasing or decreasing the absorption of the medication or even delaying the action of the drugs.

One of the most common clasification of drugs that can interact with grapefruit is the statins which are cholesterol lowering drugs. Look for the warning label on these if you or your parents are on thses drugs. If in doubt, ask the pharmacist.

Some other common drugs that can be affected by grapefruit include oxycodone (i.e. Percocet, Oxycontin)  cyclosporin (immunosuppresant drugs used in Crohn's diseases or after organ transplant),  buspirone (Buspar),  nifedipine (Lisinopril), clopidogrel (Plavix) and fexofenadine (Allegra).

Anticancer agents, Erythromycin, Quinidine, and amyodorone (i.e. Nextarone or Cordarone) can have the tosades de pointes effect with potential fatal heart rate issues.

Always ask your pharmacist about food and drug interactions.  If possible, use one pharmacy so all of your medications and history can be overseen by a pharmacist. Be safe!

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