Did you know that eating one whole grapefruit or drinking about 6 ounces of juice can alter the efficacy of many prescribed medications. This includes such favorites as cholesterol-lowering statins, anti-histamines,antidepressants, calcium channel blockers and some HIV drugs. This interaction was first reported 20 years ago and currently about 85 drugs are potentially affected.
The problem with grapefruit, as well as Seville oranges, pomelos and limes, is that some substances found in the juice inhibit an enzyme found in the intestines and liver that aids in metabolizing the drugs. The result of this inhibition is that you end up with a higher level of the active ingredient in your bloodstream. This can lead to adverse effects such as acute kidney failure, heart problems, kidney failure, trouble breathing and gastrointestinal bleeding.
This interaction occurs quickly and can last 24 hours or longer. The effects vary from person to person, but older people are at higher risk. The danger is also greater for drugs that have little forgiveness if the dose is off by even the slightest amount.
The bottom line, if you take a prescription medication, is to check with your health care professional. before consuming grapefruit or other juices mentioned above. If there is an interaction and if you want to stay out of trouble stop drinking grapefruit juice. Try orange or tangerine juice instead.