LONDON, Ontario, March 21 (UPI) -- "Fooling around with grapefruit juice" to increase the potency of a given drug "is not a good idea," says the Canadian researcher who discovered the effect.
David Bailey of the London, Ontario, Health Sciences Center said the problem is that people have varying levels of the enzyme CYP 3A4 in their intestines.
Grapefruit juice interferes with the enzyme and allows more of an orally taken drug to enter a patient's bloodstream.
"You can't just lower your dose of Lipitor and increase your consumption of grapefruit juice," Bailey told The New York Times. "There's no uniformity from one individual to another or from one bottle of grapefruit juice to the next."
Since Bailey accidentally discovered the effect in 1989, research has shown grapefruit juice can increase the potency of cholesterol-lowering drugs Lipitor, Mevacor and Zocor and interfere with some drugs used to treat depression.
Bailey says the simplest solution is to avoid grapefruit juice when taking medications.