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Ubiquinone

Scientific Name(s): Coenzyme Q-10, Mitoquinone, Ubidecarenone
Common Name(s): Adelir, Coenzyme Q10, Heartcin, Inokiton, Neuquinone, Taidecanone, Ubiquinone, Udekinon

Medically reviewed by Drugs.com. Last updated on Nov 22, 2022.

Clinical Overview

Use

Ubiquinone may have applications in cardiovascular disease, especially congestive heart failure (CHF), although there is a lack of consensus. Studies in neurological disorders are less promising. Limited clinical trials have been conducted to support widespread use for other conditions.

Dosing

Cardiovascular and neurologic trials predominantly use ubiquinone dosages of 300 mg/day or idebenone dosages of 5 mg/kg/day. Higher dosages of ubiquinone (up to 3,000 mg/day) have been used. Pharmacokinetic studies suggest split dosing is superior to single daily dosing.

Contraindications

Absolute contraindications have not been identified.

Pregnancy/Lactation

Information regarding safety and efficacy in pregnancy and lactation is lacking.

Interactions

Findings are conflicting.

Adverse Reactions

Adverse effects are rare and include diarrhea, GI discomfort, headache, loss of appetite, and nausea. Allergic reactions have been reported.

Toxicology

An observed intake safety level of 1,200 mg/day is based on clinical data; however, dosages exceeding this amount have been used with no apparent adverse effect. No accumulation in plasma or tissue following cessation of coenzyme Q10 consumption has been noted.

Source

Ubiquinones are a class of lipid-soluble benzoquinones that are involved in mitochondrial electron transport. They are found in the majority of aerobic organisms, from bacteria to mammals, hence the name ubiquinone ("ubiquitous quinone").

History

The first ubiquinone was isolated in 1957. Since that time, ubiquinones have been studied extensively in Japan, Russia, and Europe, with research in the United States beginning more recently. Popular press accounts claim that roughly 12 million Japanese people use ubiquinones as the medication of choice for management of cardiovascular diseases, supplied via more than 250 commercially available preparations. Ubiquinone is touted as an effective treatment for CHF, cardiac arrhythmias, hypertension, and in reducing hypoxic injury to the myocardium. Other claims include increases in exercise tolerance, stimulation of the immune system, and counteraction of the aging process. Ubiquinone has not been approved for therapeutic use in the United States; however, it is available as a food supplement.1

Chemistry

Ubiquinones participate in oxidation-reduction reactions in the mitochondrial respiratory chain. They also have properties of hydrogen carriers, providing a coupling of proton translocation to respiration by means of a chemiosmotic mechanism. Ubiquinol (the reduced form of ubiquinone), present in all cellular membranes, is a recognized antioxidant that can reduce oxidized tocopherol and ascorbate after free radicals have been removed. Other membrane-related functions have been identified for coenzyme Q10, including the activation of the sodium/hydrogen ion antiporter, apoptosis control, and nicotinamide adenine dinucleotide/nicotinamide/adenine dinucleotide hydrogen ratio control. Reviews of the actions of coenzymes have been published.1, 2

Laboratory monitoring of coenzyme Q10 is possible using high-performance liquid chromatography with ultraviolet, coulometric assay or electrochemical detection.3

Uses and Pharmacology

Cancer

The coadministration of ubiquinone with tamoxifen mitigated the hyperlipidemia associated with tamoxifen, and tumor marker levels indicated an antiangiogenesis effect.(39) An Agency for Healthcare Research and Quality review of clinical trials reported no evidence to support the use of ubiquinone in the prevention or treatment of cancer.(40)

Cardiovascular disease

The American College of Cardiology does not support the use of coenzyme Q10 in cardiovascular disease because a mortality benefit has not been established(4) while the Agency for Healthcare Research and Quality finds no convincing evidence to either support or refute coenzyme Q10's place in therapy.(5) Likewise, the clinical practice guideline from the American College of Physicians/American College of Cardiology Foundation/American Heart Association/American Association for Thoracic Surgery/Preventive Cardiovascular Nurses Association/Society of Thoracic Surgeons regarding management of stable ischemic heart disease (2012) recommend that treatment with garlic, coenzyme Q10, selenium, or chromium should not be used with the intent of reducing cardiovascular risk or improving outcomes in patients with stable ischemic heart disease (strong recommendation; low-quality evidence). The focused update (2014) of recommendations affected by evolving data or opinion made no new or additional comment regarding the use of these natural products(58, 74)

Clinical data

Cardiac risk in renal disease

Patients with end-stage renal disease have a high prevalence of oxidative stress that increases their cardiovascular risk. Ubiquinone was administered for 4 months at 2 doses in a double-blind, randomized, placebo-controlled trial (n=65) to patients undergoing maintenance hemodialysis 3 times weekly to assess the effects on biomarkers of oxidative stress and cardiac function. A significantly higher mean redox ratio (reduced to oxidized CoQ10) was observed in the CoQ10 1,200 mg/day (P<0.001) but not the 600 mg/day group after adjusting for baseline values. Similarly, the mean plasma concentration of the oxidative stress biomarker F2-isoprstanes was significantly improved in the higher dose group (P=0.002) compared to placebo, which held true at 2 (P=0.005) and 4 months (P<0.001) after adjusting for baseline values. Cardiac function markers were not significantly different in either intervention group in the intent-to-treat analysis, however patients in the 1,200 mg/day CoQ10 group had significantly improved isofurans, troponin T, and N-terminal pro-brain natriuretic peptide in the per-protocol analyses (n=58; P<0.05). Treatment was generally well tolerated with overall adverse event rates of 1.3 and 0.45 for the 600-mg and 1,200-mg groups, respectively, and 0.25 for placebo. Gastrointestinal discomfort and difficulty chewing the wafer doseform were reported by 3 patients in the CoQ10 groups.(63)

Cardiac surgery/Cardiac arrest

The use of coenzyme Q10 in improving mitochondrial function has been evaluated in cardiac surgery. A review was published of 8 studies, in which improvements in contractility of the myocardial tissue were demonstrated in association with increases in serum coenzyme Q10.(6, 7) Doses of coenzyme Q10 300 mg daily for 2 weeks prior to surgery were evaluated versus placebo.(6) A randomized, placebo-controlled trial evaluated coenzyme Q10 450 mg in divided doses in conjunction with hypothermia after cardiac arrest. Increased survival was shown for the coenzyme Q10 group.(8)

Congestive heart failure

Several meta-analyses and systematic reviews of clinical trials in CHF have been published, with results generally being more consistent for CHF than with other disease states.(4, 7, 9, 10, 11, 12, 13, 14, 66) The inclusion of 2 trials in which coenzyme Q10 failed to show an effect greater than placebo in these analyses, results in only a trend in favor of ubiquinone in improving cardiac function (an increase in resting ejection fraction of 1.9% [95% confidence interval [CI], −0.13% to 3.9%]).(4, 7, 9, 12) In a meta-analysis that included trials with a crossover or parallel-arm design, a 3.7% absolute difference in resting ejection fraction was found for coenzyme Q10 (95% CI, 1.59 to 5.77).(7, 11) The studies, however, either do not evaluate or are underpowered to evaluate mortality outcomes.(7, 11, 15) Because differing ubiquinone preparations were used in the studies, both the bioavailability of the compound(7, 16) and the adequacy of dosing to reach sufficient plasma coenzyme Q10 levels for effect have been questioned.(13, 14) A systematic review that included 7 randomized trials and 914 patients who had received coenzyme Q10 or placebo demonstrated no significant effect on left ventricular ejection fraction or exercise capacity.(66)

In the Q-SYMBIO trial, 420 patients with chronic NYHA functional class III or IV heart failure were randomized to receive either coenzyme Q10 (100 mg 3 times daily) or placebo, in addition to standard therapy. Patients in coenzyme Q10 group had lower rates of cardiovascular mortality (9% vs 16%), all-cause mortality (10% vs18%), and incidence of hospitalization for heart failure at 2 years. NYHA class was improved in the coenzyme Q10 group.(67)

Coenzyme Q10 is not recommended as a therapy for heart failure in the 2013 American College of Cardiology/American Heart Association guidelines.(68)

Endothelial function

The effect of a combination of red yeast rice plus ubiquinone on endothelial function and arterial stiffness was investigated in a double-blind, randomized, placebo-controlled trial in pharmacologically untreated hypercholesterolemic adults (n=40). Total and low-density lipoprotein-cholesterol levels improved significantly, starting after 2 months of administration, in patients randomized to treatment (10 mg monacolins from Monascus purpureus and 30 mg emulsioned coenzyme Q10) compared to placebo (P<0.05). Significant improvements were also seen in the vascular parameters; endothelial reactivity improved +6% with treatment and changed −0.3% with placebo (P<0.05). Additionally, a significant benefit was observed in arterial stiffness measurements with red yeast rice-coenzyme Q10 (P<0.05). No significant changes were documented between groups in triglycerides, high-density lipoprotein-cholesterol, glucose, transaminases, creatine, or creatine phosphokinase.(62)

Hypertension

Systematic reviews and meta-analyses have been conducted evaluating coenzyme Q10 in hypertension versus placebo. Trials comparing coenzyme Q10 with conventional therapy are lacking.(7, 12, 17) Decreases in systolic pressure were found in some patients. However, confounding variables, small trial size, and variable study designs make extrapolation of the data difficult.(7, 12, 71) A 2016 updated Cochrane review concluded CoQ10 supplementation did not significantly change systolic or diastolic blood pressure based on pooled data from 2 randomized clinical trials (N=50).(71)

Friedreich ataxia (hypertrophic cardiomyopathy)

Most studies used an open-label design.(7, 18) Idebenone, an analog of coenzyme Q10, was commonly employed in these trials at dosages of 5 mg/kg/day to a maximum of 300 mg/day(19) and used for periods of 6 months to 5 years.(19, 20, 21, 22, 23) Increases in heart and skeletal muscle bioenergetics are reported for all the studies, as well as decreases in ventricular hypertrophy (left ventricular mass index).(19, 20, 21, 22, 23) Results for fractional shortening and ejection fraction are mixed, with 1 study reporting a deterioration(23) and another citing improvement in cardiac function.(22)

Reversal of statin-induced myopathy

Statins (HMG-CoA reductase inhibitors) deplete circulating coenzyme Q10 levels by interfering with its biosynthesis.(7, 10, 24) Most studies indicate a correlation between the decrease in serum coenzyme Q10 and decreases of total and low-density lipoprotein cholesterol levels. This effect may be particularly important in elderly patients, in whom coenzyme Q10 levels are already compromised, and is also associated with higher dosages (lower dosages do not seem to affect intramuscular levels of coenzyme Q10).(24, 25) The use of ezetimibe alone or in combination with a statin does not offer protection against depletion of coenzyme Q10.(10, 24) No correlation has been established for decreased serum coenzyme Q10 and cardiovascular events.(7, 24) Supplemental coenzyme Q10 increased circulating levels of the compound. However, results from randomized clinical trials are inconsistent in showing an effect on statin-associated myopathy.(3, 16, 24, 26)

Results of a meta-analysis of high-quality randomized, controlled trials (6 studies, N=226) found no benefit of supplemental coenzyme Q10 on plasma creatine kinase levels and equivocal results for muscle pain. Dosages ranged from 100 to 400 mg/day given for 30 to 90 days.(69) Similarly, no significant overall effect of coenzyme Q10 was found on statin-induced myalgia compared to placebo in a meta-analysis of 7 randomized, controlled trials (N=321) with 100 to 300 mg/day given for the same duration. The number of patients remaining on statin therapy was also not impacted by administration of coenzyme Q10.(70) In contrast, pooled data from 9 randomized controlled trials (n=433) in a 2018 meta-analysis demonstrated significant improvement with CoQ10 on statin-associated muscle symptoms including pain (P<0.001), weakness (P=0.006), cramps (P<0.001), and tiredness (P<0.001) compared to placebo using a fixed-effect model. Dosages ranged from 100 to 600 mg/day given for 1 to 3 months. Significance was retained for muscle pain and muscle weakness using the randomized effect model. However, plasma creatine kinase was not significantly affected with CoQ10 supplementation compared to placebo based on data pooled from 10 randomized clinical trials (n=462).(72)

Deficiencies of coenzyme Q10

Deficiencies of coenzyme Q10 have been described, predominantly affecting children, in a spectrum of diseases including infantile-onset, multisystem diseases, as well as adult-onset cerebellar ataxia and pure myopathies.(28, 29) Lymphocyte and platelet coenzyme Q10 levels were lower in Down syndrome(41) while lower serum levels are associated with phenylketonuria and mevalonic aciduria.(42)

Diabetes

A systematic review and meta-analysis of 7 randomized controlled trials conducted in diabetic patients (n = 356) treated with ubiquinone (coenzyme Q10) for at least 12 weeks found that neither coenzyme Q10 alone or in combination with fenofibrate improved glycemic control, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, or blood pressure. However, triglycerides were significantly improved with coenzyme Q10 monotherapy (mean difference, −0.26 mmol/L; P = 0.02). When combined with fenofibrate, triglycerides (−0.72 mmol/L; P = 0.0004) and cholesterol were significantly reduced (mean difference, −0.45 mmol/L, P = 0.02). Treatment ranged from 100 to 200 mg for 3 to 6 months.(61)

Male fertility

A 2014 Cochrane systematic review and meta-analysis on antioxidants for use in male subfertility identified 3 trials (N=479) that investigated coenzyme Q10; however, extremely high heterogeneity prevented pooling of the results. The authors suggested that compared to placebo, an effect was evident at 6 months for coenzyme Q10 on sperm motility and concentration, but data were unsuitable to draw a clear conclusion.(64)

Migraine

Coenzyme Q10 has been evaluated in migraine versus placebo in small trials. Decreases in attack frequency, days with headache, and days with nausea were found for a daily dose of 300 mg.(38) However, pooled data from 2 trials (N=97) indicated no statistically significant difference in migraine frequency per month or duration (hours) between coenzyme Q10 and placebo based on moderate strength of evidence. Similar results were found for secondary outcomes (ie, severity, duration in days).(73)

The Canadian Headache Society guidelines for migraine prophylaxis (2012) strongly recommends coenzyme Q10 (100 mg 3 times daily) to eligible patients for migraine prophylaxis based on one low quality controlled trial, as does the European Federation of Neurological Societies guidelines (2009) on the treatment of migraines, considering coenzyme Q10 (300 mg daily) as third line therapy (probable efficacy) for migraine prophylaxis based on one placebo-controlled trial. (55, 56) The Scottish Intercollegiate Guidelines on headache (2008) also discusses the use of coenzyme Q10 as superior to placebo in a single small study. No recommendation regarding use is provided.(57)

Neurological disorders

The case for coenzyme Q10 as a treatment option in neurological (mitochondrial-related) disease is not as strong.(27) The role of coenzyme Q10 in Parkinson, Alzheimer, and Huntington diseases; amyotrophic lateral sclerosis; and Friedreich ataxia is postulated but not established.(2, 28, 29) The European Federation of Neurological Sciences guidelines on the clinical management of amyotrophic lateral sclerosis (2012) mention that evidence from controlled trials with coenzyme Q10 demonstrated no therapeutic benefit. No recommendation regarding its use is provided.(52)

Studies in Friedreich and non-Friedreich ataxia have largely shown a continued worsening of disease, as measured by the International Cooperative Ataxia Group rating scale, irrespective of idebenone use (5 mg/kg/day).(19, 20, 23, 30, 31)

A link between mitochondrial dysfunction and Parkinson disease has been established, but the relationship with coenzyme Q10 has not.(32) A multicenter clinical trial found a decrease in worsening of symptoms in patients with early Parkinson disease receiving coenzyme Q10 1,200 mg/day, but not at lower dosages.(33) Effects were not apparent at 1 month, but were evident at 8 months. Changes in daily living factors were more pronounced than clinical disease progression changes.(32, 34) Increases in plasma coenzyme Q10 were recorded.(33) A larger trial using higher dosages (coenzyme Q10 600 mg chewable wafers 4 times a day) found a mean change in total rating score high enough to warrant a phase 3 trial(35); however, the trial was not designed to evaluate efficacy.(34, 35) A phase 3, multicenter, double-blind randomized clinical trial (n = 600) found no evidence of benefit of coenzyme Q10 1,200 or 2,400 mg/day versus placebo in adults with early Parkinson disease not yet requiring dopaminergic therapy.(60) The study was terminated early due to futility analysis; mean follow-up time was 10.4 months. Treatment was well tolerated.(60) A multicenter trial of patients receiving anti-Parkinson medication found no difference in symptoms over placebo.(36)

The role of mitochondrial stress in Alzheimer disease led to more studies of coenzyme Q10.(31) Multicenter clinical trials using idebenone dosages of up to 360 mg 3 times a day found no effect on the rate of decline over placebo. Analyses using various rating scales showed some differences that were not considered clinically important, mirroring other older trials.(37) Similarly, no slowing of decline was noted in Huntington disease.(3) The American Academy of Neurology evidence-based guidelines regarding the treatment of chorea in Huntington disease (2012) conclude that coenzyme Q10 (300 mg twice daily) is likely ineffective in moderately improving Huntington disease chorea based on a well-controlled, randomized trial. Modest benefit can not be excluded.(53)

Ubiquinone 400 mg once daily was evaluated for treatment of diabetic polyneuropathy in a small randomized, double-blind, 12-week study in adults with type 2 diabetes mellitus and hemoglobin A1c levels less than 12. Ubiquinone was significantly better than placebo for outcomes including neuropathy symptom and impairment scores, nerve conduction velocities, and lipid peroxidation.(59)

Prader-Willi syndrome

In infants with Prader-Willi syndrome, coenzyme Q10 had no effect on lean mass versus growth hormone.(43)

Dosing

Several dosage forms exist, including compressed and chewable tablets, powder-filled and gel-filled capsules, liquid syrups, wafers, and newer solubilized formulations. The reduced form of coenzyme Q10, ubiquinol, is also commercially available.44

Pharmacokinetic studies suggest split dosing is superior to single daily dosing; for tissue uptake and crossing the blood-brain barrier, plasma coenzyme Q10 levels need to be higher than normal.44

Cardiovascular and neurologic trials predominately use ubiquinone dosages of 300 mg/day4, 7, 9, 10, 11, 12, 13, 14 or idebenone dosages of 5 mg/kg/day.19, 20, 21, 22, 23 A dose of 1,200 mg/day (but not 600 mg/day) showed promise in patients with end-stage renal disease at high cardiac risk.63 A diabetic neuropathy study used a daily dose of 400 mg.59

High-dose ubiquinone (1,200 mg/day) was used in patients with early Parkinson disease33 while dosages of 2,700 to 3,000 mg/day were used in amyotrophic lateral sclerosis trials.45, 46 An open-label study that included children evaluated tolerability of high-dose idebenone. Daily dosages of 60 mg/kg given in 3 divided doses were used for 1 month.47

Pregnancy / Lactation

Information regarding safety and efficacy in pregnancy and lactation is lacking.

Interactions

Vitamin K Antagonists: Coenzyme Q-10 may diminish the anticoagulant effect of Vitamin K Antagonists. Coenzyme Q-10 may enhance the anticoagulant effect of Vitamin K Antagonists. Monitor therapy.48, 65

Adverse Reactions

One serious adverse event, severe gastrointestinal bleeding associated with angiodysplasia, has been considered to be possibly associated with the use of ubiquinone.60 Allergic reactions, including tongue swelling, were reported in a clinical trial.35 One open-label clinical trial involving severely affected patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes syndrome reported 2 deaths.49 On autopsy, fibrotic changes in the myocardium were observed, but a causal relationship with coenzyme Q10 was not established.50

Clinical trials evaluating high-dose idebenone found only mild GI effects, headache, and fatigue.47 Similarly, clinical trials reported mild GI effects (dyspepsia, loose stools, nausea, vomiting) for ubiquinone.45, 46, 47, 50 Urine discoloration has also been noted, with no abnormalities in urine laboratory indices.47

Potential adverse effects include abdominal discomfort, headache, nausea, and vomiting. Use with caution in patients with hepatic dysfunction.51

Toxicology

A review of animal experiments and clinical trials has estimated an acceptable daily intake for coenzyme Q10 to be 12 mg/kg (ie, 720 mg/day for a 60 kg person) based on a no-observed-adverse-effect level in rats of 1,200 mg/kg/day. An observed safety level based on clinical data is given as 1,200 mg/day. No accumulation in plasma or tissue following cessation of coenzyme Q10 consumption was noted and endogenous biosynthesis was not affected.51

Index Terms

References

Disclaimer

This information relates to an herbal, vitamin, mineral or other dietary supplement. This product has not been reviewed by the FDA to determine whether it is safe or effective and is not subject to the quality standards and safety information collection standards that are applicable to most prescription drugs. This information should not be used to decide whether or not to take this product. This information does not endorse this product as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this product. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this product. This information is not specific medical advice and does not replace information you receive from your health care provider. You should talk with your health care provider for complete information about the risks and benefits of using this product.

This product may adversely interact with certain health and medical conditions, other prescription and over-the-counter drugs, foods, or other dietary supplements. This product may be unsafe when used before surgery or other medical procedures. It is important to fully inform your doctor about the herbal, vitamins, mineral or any other supplements you are taking before any kind of surgery or medical procedure. With the exception of certain products that are generally recognized as safe in normal quantities, including use of folic acid and prenatal vitamins during pregnancy, this product has not been sufficiently studied to determine whether it is safe to use during pregnancy or nursing or by persons younger than 2 years of age.

1. Crane FL. Discovery of ubiquinone (coenzyme Q) and an overview of function. Mitochondrion. 2007;7(suppl):S2-S7.17446142
2. Crane FL. The evolution of coenzyme Q. BioFactors. 2008;32(1-4):5-11.19096095
3. Steele PE, Tang PH, DeGrauw AJ, Miles MV. Clinical laboratory monitoring of coenzyme Q10 use in neurologic and muscular diseases. Am J Clin Pathol. 2004;121(suppl):S113-S120.15298157
4. Vogel JH, Bolling SF, Costello RB, et al; American College of Cardiology Foundation Task Force on Clinical Expert Consensus Documents. Integrating complementary medicine into cardiovascular medicine. A report of the American College of Cardiology Foundation Task Force on Clinical Expert Consensus Documents (Writing Committee to Develop an Expert Consensus Document on Complementary and Integrative Medicine). J Am Coll Cardiol. 2005;46(1):184-221.15992662
5. Shekelle P, Morton S, Hardy M. Effect of Supplemental Antioxidants Vitamin C, Vitamin E, and Coenzyme Q10 for the Prevention and Treatment of Cardiovascular Disease. Evidence Report/Technology Assessment No. 83 (Prepared by Southern California-RAND Evidence-based Practice Center, under Contract No 290-97-0001). AHRQ Publication No. 03-E043. Rockville, MD: Agency for Healthcare Research and Quality; 2003. http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=hserta&part=A123449. Accessed March 3, 2010.
6. Rosenfeldt F, Marasco S, Lyon W, et al. Coenzyme Q10 therapy before cardiac surgery improves mitochondrial function and in vitro contractility of myocardial tissue. J Thorac Cardiovasc Surg. 2005;129(1):25-32.15632821
7. Pepe S, Marasco SF, Haas SJ, Sheeran FL, Krum H, Rosenfeldt FL. Coenzyme Q10 in cardiovascular disease. Mitochondrion. 2007;7(suppl):S154-S167.17485243
8. Damian MS, Ellenberg D, Gildemeister R, et al. Coenzyme Q10 combined with mild hypothermia after cardiac arrest: a preliminary study. Circulation. 2004;110(19):3011-3016.15520321
9. Soja AM, Mortensen SA. Treatment of congestive heart failure with coenzyme Q10 illuminated by meta-analyses of clinical trials. Mol Aspects Med. 1997;18(suppl):S159-S168.9266518
10. Littarru GP, Tiano L. Clinical aspects of coenzyme Q10: an update. Curr Opin Clin Nutr Metab Care. 2005;8(6):641-646.16205466
11. Sander S, Coleman CI, Patel AA, Kluger J, White CM. The impact of coenzyme Q10 on systolic function in patients with chronic heart failure. J Card Fail. 2006;12(6):464-472.16911914
12. Bonakdar RA, Guarneri E. Coenzyme Q10. Am Fam Physician. 2005;72(6):1065-1070.16190504
13. Sinatra ST. Metabolic cardiology: an integrative strategy in the treatment of congestive heart failure. Altern Ther Health Med. 2009;15(3):44-52.19472864
14. Singh U, Devaraj S, Jialal I. Coenzyme Q10 supplementation and heart failure. Nutr Rev. 2007;65(6, pt 1):286-293.17605305
15. Adarsh K, Kaur H, Mohan V. Coenzyme Q10 (Coenzyme Q10) in isolated diastolic heart failure in hypertrophic cardiomyopathy (HCM). Biofactors. 2008;32(1-4):145-149.19096110
16. Young JM, Florkowski CM, Molyneux SL, et al. Effect of coenzyme Q(10) supplementation on simvastatin-induced myalgia. Am J Cardiol. 2007;100(9):1400-1403.17950797
17. 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):1112-1117.11780680
18. Cooper JM, Schapira AH. Friedreich's ataxia: coenzyme Q10 and vitamin E therapy. Mitochondrion. 2007;7(suppl 1):S127-S135.17485244
19. Buyse G, Mertens L, Di Salvo G, et al. Idebenone treatment in Friedreich's ataxia: neurological, cardiac, and biochemical monitoring. Neurology. 2003;60(10):1679-1681.12771265
20. Mariotti C, Solari A, Torta D, Marano L, Fiorentini C, Di Donato S. Idebenone treatment in Friedreich patients: one-year-long randomized placebo-controlled trial. Neurology. 2003;60(10):1676-1679.12771264
21. Hausse AO, Aggoun Y, Bonnet D, et al. Idebenone and reduced cardiac hypertrophy in Friedreich's ataxia. Heart. 2002;87(4):346-349.11907009
22. Hart PE, Lodi R, Rajagopalan B, et al. Antioxidant treatment of patients with Friedreich ataxia: four-year follow-up. Arch Neurol. 2005;62(4):621-626.15824263
23. Ribaï P, Pousset F, Tanguy ML, et al. Neurological, cardiological, and oculomotor progression in 104 patients with Friedreich ataxia during long-term follow-up. Arch Neurol. 2007;64(4):558-564.17420319
24. Marcoff L, Thompson PD. The role of coenzyme Q10 in statin-associated myopathy: a systematic review. J Am Coll Cardiol. 2007;49(23):2231-2237.17560286
25. Laaksonen R, Jokelainen K, Sahi T, Tikkanen MJ. Decreases in serum ubiquinone concentrations do not result in reduced levels in muscle tissue during short-term simvastatin treatment in humans. Clin Pharmacol Ther. 1995;57(1):62-66.7828383
26. Caso G, Kelly P, McNurlan MA, Lawson WE. Effect of coenzyme q10 on myopathic symptoms in patients treated with statins. Am J Cardiol. 2007;99(10):1409-1412.17493470
27. Marriage B, Clandinin MT, Glerum DM. Nutritional cofactor treatment in mitochondrial disorders. J Am Diet Assoc. 2003;103(8):1029-1038.12891154
28. Quinzii CM, Hirano M, DiMauro S. CoQ10 deficiency diseases in adults. Mitochondrion. 2007;7(suppl 1):S122-S126.17485248
29. Quinzii CM, López LC, Naini A, DiMauro S, Hirano M. Human CoQ10 deficiencies. Biofactors. 2008;32(1-4):113-118.19096106
30. Lamperti C, Naini A, Hirano M, et al. Cerebellar ataxia and coenzyme Q10 deficiency. Neurology. 2003;60(7):1206-1208.12682339
31. Schapira AH. Mitochondrial disease. Lancet. 2006;368(9529):70-82.16815381
32. Schapira AH, Olanow CW. Neuroprotection in Parkinson disease: mysteries, myths, and misconceptions. JAMA. 2004;291(3):358-364.14734599
33. Shults CW, Oakes D, Kieburtz K, et al; Parkinson Study Group. Effects of coenzyme Q10 in early Parkinson disease: evidence of slowing of the functional decline. Arch Neurol. 2002;59(10):1541-1550.12374491
34. LeWitt PA. Clinical trials of neuroprotection for Parkinson's disease. Neurology. 2004;63(7 suppl 2):S23-S31.15477583
35. NINDS NET-PD Investigators. A randomized clinical trial of coenzyme Q10 and GPI-1485 in early Parkinson disease. Neurology. 2007;68(1):20-28.17200487
36. Storch A, Jost WH, Vieregge P, et al; German Coenzyme Q(10) Study Group. Randomized, double-blind, placebo-controlled trial on symptomatic effects of coenzyme Q(10) in Parkinson disease. Arch Neurol. 2007;64(7):938-944.17502459
37. Thal LJ, Grundman M, Berg J, et al. Idebenone treatment fails to slow cognitive decline in Alzheimer's disease. Neurology. 2003;61(11):1498-1502.14663031
38. Sándor PS, Di Clemente L, Coppola G, et al. Efficacy of coenzyme Q10 in migraine prophylaxis: a randomized controlled trial. Neurology. 2005;64(4):713-715.15728298
39. Sachdanandam P. Antiangiogenic and hypolipidemic activity of coenzyme Q10 supplementation to breast cancer patients undergoing tamoxifen therapy. Biofactors. 2008;32(1-4):151-159.19096111
40. Coulter I, Hardy M, Shekelle P, et al. Effect of the Supplemental Use of Antioxidants Vitamin C, Vitamin E, and Coenzyme Q10 for the Prevention and Treatment of Cancer. Evidence Report/Technology Assessment Number 75 (Prepared by Southern California Evidence-based Practice Center under Contract No. 290-97-0001). AHRQ Publication No. 03-E047. Rockville, MD: Agency for Healthcare Research and Quality; 2003. http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=hserta&part=A113485. Accessed March 3, 2010.
41. Tiano L, Padella L, Carnevali P, et al. Coenzyme Q10 and oxidative imbalance in Down syndrome: biochemical and clinical aspects. Biofactors. 2008;32(1-4):161-167.19096112
42. Hargreaves IP. Coenzyme Q10 in phenylketonuria and mevalonic aciduria. Mitochondrion. 2007;7(suppl 1):S175-S180.17442628
43. Eiholzer U, L'allemand D, Schlumpf M, Rousson V, Gasser T, Fusch C. Growth hormone and body composition in children younger than 2 years with Prader-Willi syndrome. J Pediatr. 2004;144(6):753-758.15192622
44. Bhagavan HN, Chopra RK. Potential role of ubiquinone (coenzyme Q10) in pediatric cardiomyopathy. Clin Nutr. 2005;24(3):331-338.15896419
45. Ferrante KL, Shefner J, Zhang H, et al. Tolerance of high-dose (3,000 mg/day) coenzyme Q10 in ALS. Neurology. 2005;65(11):1834-1836.16344537
46. Levy G, Kaufmann P, Buchsbaum R, et al. A two-stage design for a phase II clinical trial of coenzyme Q10 in ALS. Neurology. 2006;66(5):660-663.16534103
47. Di Prospero NA, Sumner CJ, Penzak SR, Ravina B, Fischbeck KH, Taylor JP. Safety, tolerability, and pharmacokinetics of high-dose idebenone in patients with Friedreich ataxia. Arch Neurol. 2007;64(6):803-808.17562928
48. Spigset O. Reduced effect of warfarin caused by ubidecarenone. Lancet. 1994;344(8933):1372137-3.7968059
49. Remes AM, Liimatta EV, Winqvist S, et al. Ubiquinone and nicotinamide treatment of patients with the 3243A→G mtDNA mutation. Neurology. 2002;59(8):1275-1277.12391367
50. Hidaka T, Fujii K, Funahashi I, Fukutomi N, Hosoe K. Safety assessment of coenzyme Q10 (CoQ10). Biofactors. 2008;32(1-4):199-208.19096117
51. Singh RB, Niaz MA, Rastogi SS, et al. Effect of hydrosoluble coenzyme Q10 on blood pressures and insulin resistance in hypertensive patients with coronary artery disease. J Hum Hypertens. 1999;13(3):203-208.10204818
52. EFNS Task Force on Diagnosis and Management of Amyotrophic Lateral Sclerosis; Andersen PM, Abrahams S, Borasio GD, et al. EFNS guidelines on the clinical management of amyotrophic lateral sclerosis (MALS)--revised report of an EFNS task force. Eur J Neurol. 2012;19(3):360-375.21914052
53. Armstrong MJ, Miyasaki JM; American Academy of Neurology. Evidence-based guideline: pharmacologic treatment of chorea in Huntington disease: report of the guideline development subcommittee of the American Academy of Neurology. Neurology. 2012;79(6):597-603.22815556
55. Canadian Headache Society Prophylactic Guidelines Development Group. Canadian headache society guideline for migraine prophylaxis. Can J Neurol Sci. 2012;39(2 suppl. 2):1-62.
56. Evers S, Afra J, Frese A, et al; European Federation of Neurological Societies. EFNS guideline on the drug treatment of migraine--revised report of an EFNS task force. Eur J Neurol. 2009;16(9):968-981.19708964
57. Scottish Intercollegiate Guidelines Network (SIGN). Diagnosis and management of headache in adults. A national clinical guideline. Edinburgh (Scotland): Scottish Intercollegiate Guidelines Network (SIGN); 2008 Nov (SIGN publication; no. 107). Available from URL: http://www.sign.ac.uk.
58. Qaseem A, Fihn SD, Dallas P, Williams S, Owens DK, Shekelle P; Clinical Guidelines Committee of the American College of Physicians. Management of stable ischemic heart disease: summary of a clinical practice guideline from the American College of Physicians/American College of Cardiology Foundation/American Heart Association/American Association for Thoracic Surgery/Preventive Cardiovascular Nurses Association/Society of Thoracic Surgeons. Ann Intern Med. 2012;157(10):735-743.23165665
59. Hernández-Ojeda J, Cardona-Muñoz EG, Román-Pintos LM, et al. The effect of ubiquinone in diabetic polyneuropathy: a randomized double-blind placebo-controlled study. J Diabetes Complications. 2012;26(4):352-358.22595020
60. The Parkinson Study Group QE3 Investigators. A randomized clinical trial of high-dosage coenzyme Q10 in early Parkinson disease-no evidence of benefit. JAMA Neurol. 2014 Mar 24 [epub ahead of print].24664227
61. Suksomboon N, Poolsup N, Juanak N. Effects of coenzyme Q10 supplementation on metabolic profile in diabetes: a systematic review and meta-analysis. J Clin Pharm Ther. 2015;40(4):412-418.25913756
62. Cicero AF, Morbini M, Rosticci M, D’Addato S, Grandi E, Borghi C. Middle-term dietary supplementation with red yeast rice plus coenzyme Q10 improves lipid pattern, endothelial reactivity and arterial stiffness in moderately hypercholesterolemic subjects. Ann Nutr Metab. 2016;68(3):213-219.27055107
63. Rivara MB, Yeung CK, Robinson-Cohen C, et al. Effect of coenzyme Q10 on biomarkers of oxidative stress and cardiac function in hemodialysis patients: the CoQ10 biomarker trial. Am J Kidney Dis. 2017;69(3):389-399.27927588
64. Showell MG, Mackenzie-Proctor R, Brown J, Yazdani A, Stankiewicz MT, Hart RJ. Antioxidants for male subfertility. Cochrane Database Sys Rev. 2014;(12):CD007411.25504418
65. Shalansky S, Lynd L, Richardson K, Ingaszewski A, Kerr C. Risk of warfarin-related bleeding events and supratherapeutic international normalized ratios associated with complementary and alternative medicine: a longitudinal analysis. Pharmacotherapy. 2007;27(9):1237-1247.17723077
66. Madmani ME, Yusuf Solaiman A, Tamr Agha K, et al. Coenzyme Q10 for heart failure. Cochrane Database Syst Rev. 2014;(6):CD008684.24049047
67. Mortensen SA, Rosenfeldt F, Kumar A, et al; Q-SYMBIO Study Investigators. The effect of coenzyme Q10 on morbidity and mortality in chronic heart failure: results from Q-SYMBIO: a randomized double-blind trial. JACC Heart Fail. 2014;2(6):641-649.25282031
68. Yancy CW, Jessup M, Bozkurt B, et al; American College of Cardiology Foundation; American Heart Association Task Force on Practice Guidelines. 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2013;62(16):e147-239.23747642
69. Banach M, Serban C, Sahebkar A, Ursoniu S, Rysz J, Muntner P, Toth PP, Jones SR, Rizzo M, Glasser SP, Lip GY, Dragan S, Mikhailidis DP; Lipid and Blood Pressure Meta-analysis Collaboration Group. Effects of coenzyme Q10 on statin-induced myopathy: a meta-analysis of randomized controlled trials. Mayo Clin Proc. 2015;90(1):24-34.25440725
70. Kennedy C, Koller Y, Surkova E. Effect of coenzyme Q10 on statin-associated myalgia and adherence to statin therapy: a systematic review and meta-analysis. Atherosclerosis. 2020.299:1-8.32179207
71. Ho MJ, Li EC, Wright JM. Blood pressure lowering efficacy of coenzyme Q10 for primary hypertension. Cochrane Database Syst Rev. 2016;3(3):CD007435.26935713
72. Qu H, Guo M, Chai H, Wang WT, Gao ZY, Shi DZ. Effects of coenzyme Q10 on statin-induced myopathy: An updated meta-analysis of randomized controlled trials. J Am Heart Assoc. 2018;7(19):e009835.30371340
73. Okoli GN, Rabbani R, Kashani HH, et al. Vitamins and minerals for migraine prophylaxis: A systematic review and meta-analysis. Can J Neurol Sci. 2019;46(2):224-233.30764890
74. Fihn SD, Blankenship JC, Alexander KP, et al. 2014 ACC/AHA/AATS/PCNA/SCAI/STS focused update of the guideline for the diagnosis and management of patients with stable ischemic heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines, and the American Association for Thoracic Surgery, Preventive Cardiovascular Nurses Association, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. Circulation. 2014;130(19):1749-1767. doi:10.1161/CIR.000000000000009525070666

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