Ask the Doctor – April 2009

Dear Dr. Rona,

Very recently I read a short version of your magazine (health news update) with the above article.

Under the heading for Coenzyme Q10 it states ‘ commonly prescribed pharmaceutical drugs deplete Co-Q10 levels’. I have been prescribed a beta blocker recently to treat heart problem (atrial fibrillation). I had been taking Q10 before (on my own) and my medical doctor saw no problem and actually recommended continuing taking it (a first for him).

Now your article says the beta blocker interferes with the very nutrient my heart needs. If in fact this is true, should I be stopping to take the beta blocker?

Please advise,

T. Lemieux

Dr. Rona answers:

The answer to your question is no, but you should continue to supplement with Coenzyme Q10 to avoid a deficiency.

Coenzyme Q10 is the most important nutrient for ideal heart function.  It is used by the energy producing cell organelles known as the mitochondria and is vitally important for a normal cardiac output. Studies indicate that supplementing with Coenzyme Q10 improves every measurement of cardiac function. Three months of Coenzyme Q10 supplementation can lower blood pressure in at least half the people who take it who have elevated blood pressure.  It has also been shown to be important in cancer treatment, especially in breast cancer, Parkinson’s disease and periodontal disease.

Unfortunately, beta-blockers as well as many other classes of drugs deplete Coenzyme Q10.  The best known of these drugs are “the statins”. These are the drugs most often prescribed to help lower high levels of cholesterol.  Some of the common ones are Mevacor, Lescol, Pravachol, Zocor, Lipitor and Crestor.  These all work by inhibiting enzymes (HMG CoEnzyme A reductase) in the liver that manufactures cholesterol.  This class of drugs gradually reduces Coenzyme Q10 by at least 40% over a period of a year creating such unwanted symptoms such as fatigue, weak and tired muscles, lethargy and a general sense of low energy.  A deficiency of Coenzyme Q10 can result in high blood pressure. Thus, statins can theoretically increase your risk of having a heart attack or stroke.

Beta-blockers like Metoprolol, Bisoprolol, Propranolol. Sotalol , Nadolol and numerous others also cause a gradual depletion of CoQ10.  So does the popular diabetes drug, Metformin. Tricyclic antidepressant drugs like Elavil, Sinequan and Tofranil do likewise.  The anti-psychotic drug, Haldol depletes CoQ10 and at least a dozen other nutrients. Other drugs that will cause Coenzyme Q10 deficiency are diuretic drugs (water pills used for fluid retention) such as Hydrochlorothiazide and Indapamide. As with the statins, a supplement of CoQ10 is required to prevent deficiency.  If you must be on medications, my recommendation for most people on any of these drugs is to supplement 200 mg daily with food.  Coenzyme Q10 may not be compatible with the anti-coagulant drug, Warfarin (Coumadin).  Consult your doctor if you are on this prescription drug.

If you want to read more on this nutrient, see:

Zoltan Rona, M.D., M.Sc.
1366 Yonge St. Suite 201
Toronto, ON
M4T 3A7


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Dr. Zoltan P. Rona is a graduate of McGill University Medical School (1977) and has a Masters Degree in Biochemistry and Clinical Nutrition from the University of Bridgeport in Connecticut (1984). He is the author of 11 books on natural medicine – three of which are Canadian bestsellers, The Joy of Health (1991), Return to the Joy of Health (1995), and Childhood Illness and The Allergy Connection (1997). He is co-author with Jeanne Marie Martin of The Complete Candida Yeast Guidebook (1996) and is medical editor of the Benjamin Franklin Award-winning Encyclopedia of Natural Healing (1998). He has had a private medical practice in Toronto for the past 32 years, has appeared on radio and TV as well as lectured extensively in Canada and the U.S. Visit his website for appointments, call (905) 764-8700; Office: 390 Steeles Ave. W. Unit 19, Thornhill, ON

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