Ask the Doctor – April 2008

Does L-arginine cause heart attacks?

Dear Dr. Rona,

I read your excellent article in Vitality this month where you recommend L-arginine as a supplement for testosterone supplements. However the bottle of capsules 500MG prohibits use if a patient has had a heart attack. I had one in 1988 and have since had a bypass. Would you still recommend L-arginine?    – M

Dear M,

L-arginine is a precursor of nitric oxide, a substance that improves circulation by dilating the arteries. By doing so, it reduces the risk of heart disease, lowers blood pressure and improves insulin sensitivity. It’s vasodilatation effects makes L-arginine a good alternative to the erectile dysfunction drug, Viagra.

L-arginine also is known for its ability to raise growth hormone levels thus providing anti-aging benefits such as the reduction of adipose tissue and the increase of muscle mass. L-arginine improves immune function and reduces the healing time for injuries. It also improves sperm counts and sperm mobility, thereby alleviating male infertility problems.

The issue of L-arginine causing deaths in previous heart attack victims was brought up in the Jan. 4, 2008 issue of The Journal of the American Medical Association. This was a surprising finding given that L-arginine helps enhance circulation, improving coronary artery blood flow. Viagra, the prescription drug that mimics L-arginine, probably causes heart attacks by a similar mechanism.

In this study, all of the subjects were elderly heart attack patients and were using various prescription drugs. While the addition of L-arginine to the treatment protocols may have led to the sudden deaths, there is nothing in this study that would indicate that L-arginine used alone without prescription cardiac drugs poses any danger for healthy individuals without heart disease.

If you have had a heart attack in the past, I would not risk using L-arginine at this time. Further study of this supplement is indeed warranted to establish safety guidelines for those who are in your situation.

– ZR

Email your letters to letters@vitalitymagazine.com. Visit Dr. Zoltan Rona’s website at www.mydoctor.ca/drzoltanrona