Dec 13, 2011

Can Drinking Grapefruit Juice, or Eating and Drinking Hamper the Effectiveness of a Prescription Medication?

Washing down your medicine with fruit juice may be a bad idea. Some drugs require you to eat before taking them, others require you not to eat.

Bob De Marco
Alzheimer's Reading Room

You may have heard that grapefruit juice can increase the absorption of certain drugs and potentially turn normal doses into toxic ones.

According to a research study, patients shouldn’t take statins (such as Pfizer’s Lipitor or Merck’s Zocor) with grapefruit juice, because doing so can cause the drug to build up to unhealthy levels in the body. If you read the instructions that come with prescription drugs or the labels on the bottle they specifically say not to drink grapefruit juice.

The scientist who first identified this problem finds grapefruit and other common fruit juices can do the opposite – significantly decrease the absorption of drugs, potentially canceling out the benefits of lifesaving medications, such as those that treat heart disease, cancer, organ-transplant rejection, and infection.

Here is some good advice. When you get your prescription from the doctor ask about grapefruit juice, or any other special eating and drinking restrictions associated with the drug. I also learned first hand that pharmacist are extremely helpful when asking these types of questions.

While asking our pharmacist about grapefruit juice, I learned that you should not drink or eat anything in the morning before taking thyroid medication. And, you should not eat or drink anything for an hour after taking the thyroid medication. Violating these rules could negate the benefits of the drug.

I have asked at least fifty people that are taking thyroid medication if they knew this. Every single one of them answered -- no.

Take heed. You should check. You want the prescription drug you are taking to work effectively. Research scientists work a long time trying to come up with the right dosages, and most effective way to take a given prescription medication. A medication works most effectively when you follow the instructions that come with it.

You might also consider reading the disclosure document that comes with every new prescription. This is where you learn about potential side effects. I would strongly suggest this with Alzheimer's medications.

Alzheimer's Disease -- Advice and Insight



Original content Bob DeMarco, the Alzheimer's Reading Room