Drug Database - Coenzyme Q10 (CoQ10)
Coenzyme Q10, Co Q10, Ubiquinone, Vitamin Q
Coenzyme Q10 (CoQ10) is produced by the human body and is necessary for the basic
functioning of cells. CoQ10 levels are reported to decrease with age and to be low in
patients with some chronic diseases such as heart conditions, muscular dystrophies,
Parkinson's disease, cancer, diabetes, and HIV/AIDS. Some prescription drugs may also
lower CoQ10 levels.
Levels of CoQ10 in the body can be increased by taking CoQ10 supplements, although it is
not clear that replacing "low CoQ10" is beneficial. CoQ10 has been used, recommended, or
studied for numerous conditions, but remains controversial as a treatment in many areas.
These uses have been tested in humans or animals. Safety and effectiveness have not always
been proven. Some of these conditions are potentially serious, and should be evaluated by
a qualified healthcare provider.
Coenzyme Q10 Deficiency
Coenzyme Q10 is normally produced by the human body, although deficiency may occur in
patients with impaired CoQ10 biosynthesis due to severe metabolic or mitochondrial
disorders, not enough dietary CoQ10 intake, or too much CoQ10 use by the body. Depending
on the cause of CoQ10 deficiency, supplementation or increased dietary intake of CoQ10 and
the vitamins and minerals needed to produce CoQ10 may be effective.
High Blood Pressure (Hypertension)
Preliminary research suggests that CoQ10 causes small decreases in blood pressure
(systolic and possibly diastolic). Low blood levels of CoQ10 have been found in people
with hypertension, although it is not clear if CoQ10 "deficiency" is a cause of high blood
pressure. Well-designed long-term research is needed to strengthen this recommendation.
Age-Related Macular Degeneration
Early study shows that acetyl-L-carnitine, n-3 fatty acids, and Coenzyme Q10
(Phototrop®) may help age-related macular degeneration. More research is needed using
Coenzyme Q10 alone before a recommendation can be made.
Promising preliminary evidence suggests that CoQ10 supplements may slow down, but not
cure, dementia in people with Alzheimer's disease. Additional well-designed studies are
needed to confirm these results before a firm recommendation can be made.
Angina (chest pain from clogged heart arteries)
Preliminary small human studies suggest that CoQ10 may reduce angina and improve exercise
tolerance in people with clogged heart arteries. Better studies are needed before a firm
recommendation can be made.
The below doses are based on scientific research, publications, traditional use, or expert
opinion. Many herbs and supplements have not been thoroughly tested, and safety and
effectiveness may not be proven. Brands may be made differently, with variable
ingredients, even within the same brand. The below doses may not apply to all products.
You should read product labels, and discuss doses with a qualified healthcare provider
before starting therapy.
Adults (above 18 years old)
50-1,200 milligrams of CoQ10 have been taken in divided doses by mouth daily.
- 85 milligrams of CoQ10 per milliliter of soybean oil suspension has been applied to
the surface of affected areas once weekly using a plastic syringe for gum disease.
Most studies of CoQ10 for heart protection during bypass surgery have used CoQ10 taken by
mouth. One study used intravenous CoQ10, 5 milligrams per kilogram of body weight, given
two hours prior to surgery. Safety is not clear. Any therapies used close to the time of
surgery should be discussed with the surgeon and a pharmacist prior to starting.
Children (under 18 years old)
There is not enough scientific information to recommend the safe use of CoQ10 in children.
A qualified healthcare provider should be consulted before considering use.
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements.
There is no guarantee of strength, purity or safety of products, and effects may vary. You
should always read product labels. If you have a medical condition, or are taking other
drugs, herbs, or supplements, you should speak with a qualified healthcare provider before
starting a new therapy. Consult a healthcare provider immediately if you experience side
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:
- stomach upset
- loss of appetite
- skin itching
- increased light sensitivity of the eyes
- 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.
Pregnancy and Breastfeeding
There is not enough scientific evidence to support the safe use of CoQ10 during pregnancy
or breastfeeding. Sperm may be affected.
- Berman M, Erman A, Ben Gal T, et al. Coenzyme Q10 in patients with end-stage heart
failure awaiting cardiac transplantation: a randomized, placebo-controlled study. Clin
Burke BE, Neuenschwander R, Olson RD. Randomized, double-blind, placebo-controlled trial
of coenzyme Q10 in isolated systolic hypertension. South Med J 2001;94(11):1112-1117.
- Damian MS, Ellenberg D, Gildemeister R, et al. Coenzyme Q10 combined with mild
hypothermia after cardiac arrest: a preliminary study. Circulation 2004 Nov
- Hershey AD, Powers SW, Vockell AL, et al. Coenzyme Q10 deficiency and response to
supplementation in pediatric and adolescent migraine. Headache 2007 Jan;47(1):73-80.
- Hodgson JM, Watts GF, Playford DA, et al. Coenzyme Q(10) improves blood pressure and
glycaemic control: a controlled trial in subjects with type 2 diabetes. Eur J Clin Nutr
- Khan M, Gross J, Haupt H, et al. A pilot clinical trial of the effects of coenzyme Q10
on chronic tinnitus aurium. Otolaryngol Head Neck Surg 2007 Jan;136(1):72-7.
- Langsjoen H, Langsjoen P, Langsjoen P, et al. Usefulness of coenzyme Q10 in clinical
cardiology: a long-term study. Mol Aspects Med 1994;15 Suppl:s165-s175.
- Miyake Y, Shouzu A, Nishikawa M, et al. Effect of treatment with
3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors on serum coenzyme Q10 in
diabetic patients. Arzneimittelforschung 1999;49(4):324-329.
- Morisco C, Trimarco B, Condorelli M. Effect of coenzyme Q10 therapy in patients with
congestive heart failure: a long-term multicenter randomized study. Clin Investig
- Reid MS, Casadonte P, Baker S, et al. A placebo-controlled screening trial of
olanzapine, valproate, and coenzyme Q10/L-carnitine for the treatment of cocaine
dependence. Addiction 2005 Mar;100 Suppl 1:43-57.
Rosenfeldt FL, Haas SJ, Krum H, et al. Coenzyme Q10 in the treatment of hypertension: a
meta-analysis of the clinical trials. J Hum Hypertens 2007 Apr;21(4):297-306.
- Sandor PS, Di Clemente L, Coppola G, et al. Efficacy of coenzyme Q10 in migraine
prophylaxis: a randomized controlled trial. Neurology 2-22-2005;64(4):713-715.
- Shults CW, Oakes D, Kieburtz K, et al. Effects of coenzyme Q10 in early Parkinson
disease: evidence of slowing of the functional decline. Arch Neurol 2002;59(10):1541-1550.
- Singh RB, Wander GS, Rastogi A, et al. Randomized, double-blind placebo-controlled
trial of coenzyme Q10 in patients with acute myocardial infarction. Cardiovasc Drugs Ther
- The NINDS NET-PD Investigators. A randomized clinical trial of coenzyme Q10 and
GPI-1485 in early Parkinson disease. Neurology 2007 Jan 2;68(1):20-8.