Overview:
Coenzyme Q10 (CoQ10) is a compound found naturally in the energy-producing center of the cell known as the mitochondria. CoQ10 is involved in making an important molecule known as adenosine triphosphate (ATP). ATP serves as the cell's major energy source and drives a number of biological processes, including muscle contraction and the production of protein. CoQ10 also works as an antioxidant.
Antioxidants are substances that scavenge free radicals, damaging compounds in the body that alter cell membranes, tamper with DNA, and even cause cell death. Free radicals occur naturally in the body, but environmental toxins (including ultraviolet light, radiation, cigarette smoking, and air pollution) can also increase the number of these damaging particles. Scientists believe free radicals contribute to the aging process, as well as the development of a number of health problems, including heart disease and cancer. Antioxidants, such as CoQ10, can neutralize free radicals and may reduce or even help prevent some of the damage they cause.
CoQ10 and Alzheimer’s
CoQ10 has been used, recommended, or studied for numerous conditions, but remains controversial as a treatment in many areas. There is promising preliminary evidence suggests that CoQ10 supplements may slow down, but not cure, dementia in people with Alzheimer's disease.
One of the theories of impaired memory involves lack of oxygen utilization by the brain, a function that is supported by Coenzyme Q10. The research which has been conducted on Coenzyme Q10 suggests that sufficient Coenzyme Q10 must be administered for a long enough period (usually 4-12 weeks), to achieve results, which is consistent with a buildup of enzyme activity. For instance, 60 mg of Coenzyme Q10 was administered for 6 months, along with vitamin B-6 and iron, to a 49 year old woman with Alzheimer's disease, who had a one year history of progressive memory impairment. It's believed that electron activity is reduced in Alzheimer's patients, and the lack of energy fuel may be implicated in furthuring development of the tangles seen on the nerves in Alzheimer’s. Co-enzyme Q10, of course, supports the production of electron activity and delivery of energy fuel to the nerves. Post-treatment, there was increased blood flow in the brain, faster alpha wave activity, and, "her mental state improved to almost normal after 6 months of therapy...symptoms progressed with cessation of the therapy and improved with its resumption".
However, additional well-designed studies are needed to confirm these results before a firm recommendation can be made.
Possible Interactions
If you are currently being treated with any of the following medications, you should not use CoQ10 without first talking to your health care provider.
Daunorubicin and doxorubicin -- CoQ10 may help reduce the toxic effects on the heart caused by daunorubicin (Cerubidin) and doxorubicin (Adriamycin), two chemotherapy medications that are commonly used to treat several kinds of cancer. Always speak to your oncologist before taking antioxidants along with chemotherapy.
Blood pressure medications -- In a clinical study of individuals taking blood pressure medications, including diltiazem (Cardizem), metoprolol (Lopressor or Toprol), enalapril (Vasotec), and nitroglycerin (Nitrostat or Nitrobid), CoQ10 supplementation allowed the individuals to take lower dosages of these drugs. This suggests that CoQ10 may enhance the effectiveness of certain blood pressure medications, but more research is needed to verify these results.
Blood-thinning medications -- There have been reports that CoQ10 may decrease the effectiveness of blood-thinning medications such as warfarin (Coumadin) or clopidigrel (Plavix), leading to the need for increased doses. Therefore, given that this medication must be monitored very closely for maintenance of appropriate levels and steady blood thinning, CoQ10 should be used with warfarin only under careful supervision by your health care provider.
Timolol -- CoQ10 supplementation may reduce the heart-related side effects of timolol drops (Betoptic), a beta-blocker medication used to treat glaucoma, without decreasing the effectiveness of the medication.
Other -- Medications that can lower the levels of CoQ10 in the body include statins for cholesterol , including atorvastatin (Lipitor), lovastatin (Mevacor), pravastatin (Pravachol, and simvastatin (Zocor), fibric acid derivatives for cholesterol, including gemfibrozil (Lopid), beta-blockers for high blood pressure, such as atenolol (Tenormin), labetolol (Normodyne), metoprolol (Lopressor or Toprol), and propranolol (Inderal), and tricyclic antidepressant medications, including amitriptyline (Elavil), doxepin (Sinequan), and imipramine (Tofranil).
Side Effects and Warnings
There are few serious reported side effects of CoQ10. Side effects are typically mild and brief, stopping without any treatment needed. Reactions may include nausea, vomiting, stomach upset, heartburn, diarrhea, loss of appetite, skin itching, rash, insomnia, headache, dizziness, itching, irritability, increased light sensitivity of the eyes, fatigue, or flu-like symptoms.
CoQ10 may lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a healthcare provider, and medication adjustments may be necessary.
Low blood platelet number was reported in one person taking CoQ10. However, other factors (viral infection, other medications) may have been responsible. Lowering of platelets may increase the risk of bruising or bleeding, although there is a lack of known reports of bleeding from CoQ10. Caution is advised in people who have bleeding disorders or who are taking drugs that increase the risk of bleeding. Dosing adjustments may be necessary.
CoQ10 may decrease blood pressure, and caution is advised in patients with low blood pressure or taking blood pressure medications. Elevations of liver enzymes have been reported rarely, and caution is advised in people with liver disease or taking medications that may harm the liver. CoQ10 may lower blood levels of cholesterol or triglycerides. Thyroid hormone levels may be altered based on one study.
Organ damage due to lack of oxygen/blood flow during intense exercise has been reported in a study of patients with heart disease, although the specific role of CoQ10 is not clear. Vigorous exercise is often discouraged in people using CoQ10 supplements.
Sources and Additional Information: