Thanks to research that tells us how drugs act, are metabolized (broken down and used) and eliminated from the body, your prescription drug label now comes with specific instructions about how and when the medicine should be taken and what other drugs, activities or foods should be avoided to assure the drug works as it is intended.

In the case of food, we often don't know what the food contains that causes these drug interactions because most foods, especially fruits and vegetables, can contain up to 10,000 compounds that are just now being isolated as the technical equipment that does this analysis becomes more sophisticated.

For example, grapefruit juice interacts with many drugs. Some researchers think that the grapefruit juice interferes with the natural enzymes in the body that break down some drugs so they can be eliminated from the body. That results in a buildup of the medicine which leads to unwanted side effects. The amount of grapefruit juice, in this case, that can be tolerated varies from person to person depending upon the amount of the enzyme that's captured by the grapefruit juice.

This newsletter focuses on grapefruit juice as a follow up to some media stories that remind people who take statins, the cholesterol lowering drugs, are susceptible to this interaction.

Here's a partial list of the more commonly used medication that interacts with grapefruit juice in SOME people.

Statins (Cholesterol Lowering Drugs):

• Baycol (Cerivastatin)
• Mevacor (Lovastatin)
• Lipitor (Atorvastatin)
• Zocor (Simvastatin)

Antihistamines:

• Ebastine
• Seldane (Terfenadine, taken off the U.S. market)

Calcium Channel Blockers (Blood Pressure Drugs):

• Nimotop (Nimodipine)
• Nitrendipine
• Plendil (Felodipine)
• Pranidipine
• Sular (Nisoldipine)

Psychiatric Medications:

• Buspar (Buspirone)
• Halcion (Triazolam)
• Tegretol (Carbamazepine)
• Valium (Diazepam)
• Versed (Midazolam)

Immune Suppressants:

• Neoral (Cyclosporine)
• Prograf (Tacrolimus)

Pain Medications:

• Methadone

Impotence Drug:

• Viagra (Sildenafil)

Miscellaneous:

• Losartan (for lowering blood pressure) -
• Digoxin (for treating congestive heart failure)