Daily Health News Blog

Many people taking medications have learned to be leery of grapefruit and its juice—which is too bad, since grapefruit is not only delicious, but also heart-healthy and nutritious. Here's what you need to know. Grapefruit and its juice raise blood levels of certain drugs, and the effect can be dangerous. This occurs because grapefruit contains substances that disable an enzyme (known as CYP3A4) in the small intestine that would otherwise help break down the drugs. The interaction happens fast and can last 24 hours or longer—the time it takes for your body to make new enzymes—though it trails off. On the other hand, grapefruit juice can also lower blood levels of a few drugs by reducing absorption. These effects can vary from person to person—and even from grapefruit to grapefruit. This makes the scenario highly unpredictable. The drugs include many cholesterol-lowering statins, as well as certain calcium channel blockers (for high blood pressure), tranquilizers, antihista...