Fruit juice and drug interactions

By Carrie Johnson Weimar • Published: December 17th, 2008
Category: Health in a Heartbeat

Doctors have warned parents about the dangers of feeding children too much fruit juice. The sweet liquid can fill them with empty calories and too much sugar. But now there’s another reason to say “thanks but no thanks” to the juice box. Researchers in London have found that consuming juice while taking certain drugs can wipe out the medication’s beneficial effects.

The study findings were presented at a meeting of the American Chemical Society. The researchers gave patients the allergy drug Allegra. The drug worked normally when it was taken with water, but it barely had any effect on those who consumed it with grapefruit juice.

The problem isn’t limited to allergy medication. Juice can lower the absorption of antibiotics and drugs used to treat cancer and high blood pressure or to prevent heart attacks and rejection of transplanted organs.

This isn’t the first study to reveal problems regarding the interaction of juice and medicine. Researchers have already documented the so-called Grapefruit Juice Effect, which can increase the absorption of certain drugs and lead to overdoses. However, this is the first study to show that juice may have the opposite effect.

Think you can solve the problem by cutting out grapefruit juice? Researchers say apple and orange juice contain substances similar to the active ingredient in grapefruit juice, meaning they have a similar effect.

If you’re concerned, experts recommend talking to your doctor. In the meantime, it probably wouldn’t hurt to wash your pills down with good, old-fashioned water.