Meds and you

22 July 2014

The interaction of grapefruit and medication

Love grapefruit? Doctors warn that the bitter fruit can interfere with the way certain medicines work.

Grapefruit and grapefruit juice often form part of a healthy diet. They’re high in vitamin C and potassium – both of which your body needs to function properly.

But doctors warn that grapefruit, as well as certain other citrus fruits (such as limes and Seville oranges, often used to make marmalade), can interfere with the way in which certain medicines can work. This includes both over-the-counter and prescription medication.

How grapefruit interacts with medication
Grapefruit contains furanocoumarins, a class of organic compounds that can block an enzyme that breaks down certain medications in the body. The absorption of the medication into the bloodstream is increased to the extent that the medication levels can become toxic. To your body it could appear as if you’re taking multiple doses of the same medication. In serious cases, this can ultimately lead to kidney and liver damage.

Furanocoumarins can also cause medication to be metabolised too quickly by the digestive system, not giving it enough time to do what you need it to do in order to treat a specific condition.

Grapefruit doesn’t interfere with all drugs prescribed for certain conditions, so it’s a good idea to speak to your doctor or pharmacist to find out whether it has an effect on the particular medication you could be taking. The number of medications that interact with grapefruit is on the increase, as more medicines come onto the market every year.

Drinking grapefruit juice or eating grapefruit even 12 hours after taking a pill can still have an effect on the absorption of the medication. You might have to consider cutting out grapefruit from you diet while you’re taking this medication.

Grapefruit or grapefruit juice can interact with some, but certainly not all medications, prescribed for the following conditions or diseases:

• Some blood-pressure-lowering medication
• Some anti-anxiety medication
• Some cholesterol-lowering medication
• Some organ-transplant-rejection medication
• Some anti-arrhythmia medication
• Some antihistamines

It’s important to remember that people react differently to the same medication: what affects one person badly may not have any effect on someone else. It’s therefore essential to speak to your doctor or pharmacist to find out whether the eating of grapefruit or the drinking of grapefruit juice could have a negative effect on how your body absorbs the particular medication you’re taking.

Also fall into a habit of checking the ingredients listed on the bottles of other fruit juices, as they may contain grapefruit juice.

- (Susan Erasmus, Health24)


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