The body's levels of coenzyme Q10 decrease with age. In addition, low levels of coenzyme Q10 have been seen in patients with conditions such as heart failure, HIV/AIDS, cancer, diabetes and Parkinson's disease. The use of some drugs, such as hydralazine, beta blockers and diuretics, may also lower levels of coenzyme Q10.
Researchers have had mixed results using coenzyme Q10 as a supplement to treat cardiovascular conditions such as high blood pressure, angina and heart failure. For example, preliminary studies have shown that use of the supplement (also known as ubiquinone, vitamin Q10, CoQ10 or any number of brand names) may cause a slight decrease in blood pressure.
Most of the studies performed to date have used a small number of patients who were given coenzyme Q10 for a brief period of time. These patients were also taking other medication(s) at the same time, so it's difficult to determine what benefit, if any, might have been derived from the use of coenzyme Q10.
As a result of the current state of research on this supplement, groups like the American Heart Association do not recommend its use until there is more evidence of a significant benefit from coenzyme Q10.
The use of coenzyme Q10 carries a risk of mild side effects. These may include nausea, vomiting, heartburn, diarrhea, loss of appetite, rash, insomnia, headache, dizziness, irritability, fatigue or flu-like symptoms. Coenzyme Q10 may also interfere with Coumadin (warfarin), a medication used to treat blood clots. This supplement may also lower blood sugar levels; therefore, patients with diabetes or hypoglycemia are advised to use caution if taking coenzyme Q10 supplements.
Sources:
"Coenzyme Q10." americanheart.org. 2008. American Heart Association. 16 Dec. 2008 <http://www.americanheart.org/presenter.jhtml?identifier=4564>.
"Coenzyme Q10." Complementary Medicine. 2008. University of Maryland Medical Center. 16 Dec. 2008 <http://www.umm.edu/altmed/articles/coenzyme-q10-000295.htm>.
"Coenzyme Q10." Medline Plus. 1 Mar. 2008. National Institutes of Health. 16 Dec. 2008 <http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-coenzymeq10.html>.
"Coenzyme Q10." Micronutrient Information Center. Feb. 2007. Linus Pauling Institute, Oregon State University. 16 Dec. 2008 <http://lpi.oregonstate.edu/infocenter/othernuts/coq10/>.
