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The Spokesman-Review Newspaper
Spokane, Washington  Est. May 19, 1883

Marital dispute over orange juice

Joe Graedon, M.S., and Teresa Graedon, Ph.D. King Features Syndicate

Q. I have understood that grapefruit juice generally should not be used to take medicine. My wife believes that orange juice also is dangerous. She is urging me not to take my pills with orange juice.

I understand that grapefruit juice contains an ingredient that orange juice does not and that is what interacts adversely with medicine. This is now becoming a major issue for us. Can you resolve it?

A. As with most marital disputes, the answer to your question is complicated. Scientists have known for 25 years that grapefruit juice has a special ability to increase blood levels of certain medications, including the hypertension drug felodipine, cholesterol-lowering meds such as atorvastatin and simvastatin and the anti-anxiety agent buspirone. This can make side effects more severe. The only other fruits that act like grapefruit are Seville (sour) oranges and pomelos.

Ordinary orange juice and apple juice can affect other medications in a completely different way (Journal of Clinical Pharmacology online, June 10, 2015). Instead of inhibiting the intestinal enzyme (CYP3A) that metabolizes many medicines, these fruit juices inhibit the compounds that help move certain medications into tissues and cells. The affected drugs include aliskiren (Tekturna), fexofenadine (Allegra) and atenolol (Tenormin), most notably. The impact is to lower tissue levels and effectiveness.

The grapefruit effect can last for a few days, while orange juice activity disappears within a few hours. Whether or not you need to avoid taking your medication with grapefruit or orange juice depends on which drug you are taking.

Q. I have been on metformin since I was diagnosed with diabetes several years ago. About a year ago, I developed debilitating neuropathy. Just going to the store for an hour kept me off my feet for a few days.

My podiatrist suggested a vitamin B complex. After taking it for two weeks, the difference is amazing. My feet hardly hurt at all, and I can bend my toes more than I could before. I think I’m getting a little feeling back in areas that are numb.

I read on your site that metformin can deplete B vitamins. I have suffered terribly for a year because doctors prescribe medicines without really knowing the side effects. Now I’m going to talk to my doctor about the gas and bloating I get from metformin.

A. Metformin is known to deplete vitamin B-12. Levels should be monitored regularly for those on metformin or acid-suppressing drugs, which also can reduce vitamin B-12 levels. Symptoms of B-12 deficiency include numbness, tingling, nerve pain, difficulty walking, fatigue and anemia.

We are sending you our Guide to Managing Diabetes with more information on metformin and nondrug ways that may help control blood sugar. Anyone who would like a copy, please send $3 in check or money order with a long (No. 10), stamped (70 cents), self-addressed envelope to: Graedons’ People’s Pharmacy, No. DM-11, P.O. Box 52027, Durham, NC 27717-2027. It also can be downloaded for $2 from our website: www.peoplespharmacy.com.

Q. I have occasional heart palpitations. My doctor suggested I buy a device for my phone called AliveCor. He said it would detect atrial fibrillation. Is that true?

A. The AliveCor device and app is available for iPhone and Android phones. It provides a mobile electrocardiogram that it can analyze quickly for A-fib. You can share the ECG with your doctor.

In their column, Joe and Teresa Graedon answer letters from readers. Write to them in care of this newspaper or email them via their website: www.PeoplesPharmacy.com. Their newest book is “Top Screwups Doctors Make and How to Avoid Them.”