Written by Helen Cooke and the CAM-Cancer Consortium.
Updated April 29, 2014

Co-enzyme Q10

Does it work?

Does CoQ10 work as an anti-cancer agent?

Controlled clinical studies

A trial involving 210 women undergoing tamoxifen treatment for breast cancer reported reduced levels of angiogenesis markers and lipid levels (p<0.05) in the group treated with CoQ10 (100mg) alongside tamoxifen. Tamoxifen can cause hypertriglyceridemia, increasing the risk of cardiovascular disease, so reducing lipid levels may be beneficial. The women were split into 4 groups; One group were left untreated, one group were treated for more than a year with tamoxifen, one group were followed up for 45 days after they were given instruction to take CoQ10 100mg, another group were followed up for 90 days after they were given instruction to take CoQ10 100mg, Results were compared to 42 disease-free women who acted as a control group. Methodological limitations include lack of randomisation, blinding, inappropriate control groups and questionable patient compliance issues; patients self-administered both tamoxifen and CoQ10.

Researchers who conducted a three year (non-randomised) study with a sample of melanoma patients (n=81) found that the group treated with CoQ10 (400mg) alongside interferon reported improved quality of life (favourable mood effects, reduction in physical weakness and in the severity of tinnitus) compared to the control group who received interferon only. The patients with stage II melanoma in this group also appeared to have a lower rate of metatatic recurrence at 5 year follow-up (approximately 10 times lower). A survival study could not be understaken due to the small patient sample and relatively short duration of follow-up. Methodological limitations include the use of subjective measures and lack of blinding, which leads to a potential for bias.

Pre-clinical data

There is some preliminary evidence from laboratory and animal studies that chemicals very similar to CoQ10 (analogues of CoQ10) have anti-cancer effects. One study involving mice who had been inoculated with small cell lung cancer and then given CoQ10 and single dose radiation therapy showed less inhibition of tumour growth than the mice in the control group. It was proposed the results may have been due to CoQ10’s antioxidant properties. Radiation leads to the production of free radicals, which antioxidants protect against.

Overall there is no good quality evidence to support CoQ10 working as an anti-cancer agent. The above controlled trials were not randomised or high quality clinical trials.

Does CoQ10 work as a protector against adverse effects of chemotherapeutic agents?


A Cochrane systematic review (updated in 2011) reported that no definite conclusions can be made about the efficacy of different cardioprotective agents for cancer patients receiving anthracyclines. It only included one small (n=20) randomised controlled trial on CoQ10, which did not show cardioprotective effect.

A systematic review by Roffe et al. (2004) states that there is some evidence of a protective benefit from CoQ10, however, the authors conclude that the studies reviewed are all methodologically flawed and the results not conclusive. The article reviewed six studies, three randomised and three non-randomised. The numbers of people included in the clinical studies were small, so the results need to be interpreted with caution. The review stated that many unanswered questions remain about the use of CoQ10 alongside anthracycline. Little is known about how long these effects can last for or the best way to administer CoQ10 (what levels should be taken/should it be administered with food etc).

Bryant et al. (2007) conducted a systematic review to evaluate technologies to reduce anthracycline-induced cardiotoxicity in children. The review presented the results of one study that reported a protective effective of CoQ10 on cardiac function . The review concluded it was difficult to draw conclusions because related studies were lacking, both in terms of quality and quantity.

Controlled clinical trials

All controlled clinical trials investigating whether CoQ10 protects against chemotherapy induced cardiotoxicity were included in the above systematic reviews.

Pre-clinical data

Animal evidence supporting the cardioprotective effects of CoQ10 has been seen on the heart muscles of mice, rats and rabbits given the chemotherapy drug Doxorubicin (Adriamycin),. However, the same positive benefit was not found in another study with Adriamycin and also radiotherapy. A further mice study concluded that CoQ10 ameliorated acute cisplatin nephrotoxicity.

It therefore appears that although there is some evidence that CoQ10 works as a protector against adverse effects of several chemotherapeutic drugs, further higher quality trials are still needed to confirm this.

Does CoQ10 work as a protector against chronic fatigue?

CoQ10 supports the release of energy in cells; therefore, it is theorised that chronic fatigue may sometimes be caused by a deficiency in CoQ10. Supporters of this theory suggest that supplementing the diet with CoQ10 may counteract cancer-related chronic fatigue cancer, but no trials are available.


Helen Cooke, CAM-Cancer Consortium. Co-enzyme Q10 [online document]. http://www.cam-cancer.org/CAM-Summaries/Dietary-approaches/Co-enzyme-Q10. April 29, 2014.

Document history

Assessed as up to date in April 2014 by Barbara Wider.
Revised and updated in December 2012 by Helen Cooke.
Fully revised and updated in September 2011 by Helen Cooke.
Fully revised and updated in August 2009 by Helen Cooke.
First published in 2005, authored by Helen Seers and Helen Cooke.


  1. Hathcock, J, Shao, (2006) A Risk Assessment for CoenzymeQ10(Ubiquinone). Regul Toxicol Pharm 45(3): 282-288.
  2. Ernster, L, & Forsmark-Andrée, P. Ubiquinol: an endogenous antioxidant in aerobic organisms. Clinical Investigator. 1993; 71 (8 Suppl): S60-5.
  3. Lass A, Kwong L, Sohal RS. Mitochondrial coenzyme Q content and aging. Biofactors.1999; 9(2-4):199-205.
  4. Coenzyme Q10 PDQ. National Cancer Institute. [online]. 20011 [cited 2012 Oct 04]. Available from: URL http://www.cancer.gov/cancertopics/pdq/cam/coenzymeQ10/healthprofessional/allpages
  5. Folkers, K, Osterborg, A, Nylander, M, Morita, M, & Mellstedt, H. Activities of vitamin Q10 in animal models and a serious deficiency in patients with cancer. Biochemical and Biophysical Research Communications. 1997; 234 (2): 296-9.
  6. Folkers, K. The potential of coenzyme Q 10 (NSC-140865) in cancer treatment. Cancer Chemotherapy Reports. 1974; 24 (4): 19-22.
  7. Frei B, Kim MC, Ames BN. Ubiquinol-10 is an effective lipid-soluble antioxidant at physiological concentrations. Proceedings of the Natural Academy of Science.1990; 87(12):4879-83.
  8. Folkers, K, Shizukuishi, S, Takemura, K, Drzewoski, J, Richardson, P, Ellis, J, & Kuzell, WC. Increase in levels of IgG in serum of patients treated with coenzyme Q10. Research Communication in Chemical Patholology and Pharmacology. 1982; 38 (2): 335-8.
  9. Rusciani L, Proietti I, Rusciani A, Paradisi A, Sbordoni G, Alfano C, et al. Low plasma coenzyme Q10 levels as an independent prognostic factor for melanoma progression. J Am Acad Dermatol. 2006 Feb;54(2):234-41
  10. Coenzyme Q10 PDQ. Natural Standard Database. [online].2009 [cited 2009 May 31]. Available from URL http://www.naturalstandard.com/naturalstandard/monographinfo.asp?title=Coenzyme%20Q10&file=coenzymeq10
  11. Chai W, Cooney RV, Franke AA, Shvetsov YB, Caberto CP, Wilkens LR et al. Plasma coenzyme Q10 levels and postmenopausal breast cancer risk: the multiethnic cohort study. Cancer Epidemiology, Biomarkers & Prevention 2010; 19(9):2351-2356.
  12. Cooney RV, Dai Q, Gao YT, Chow WH, Franke AA, Shu XO et al. Low plasma coenzyme q10 levels and breast cancer risk in chinese women. Cancer Epidemiology, Biomarkers & Prevention 2011; 20(6):1124-1130.
  13. Chai W, Cooney RV, Franke AA, Caberto CP, Wilkens LR, Le ML et al. Plasma coenzyme Q10 levels and prostate cancer risk: the multiethnic cohort study. Cancer Epidemiology, Biomarkers & Prevention 2011; 20(4):708-710.
  14. Conklin, K. A. (2005). "Coenzyme q10 for prevention of anthracycline-induced cardiotoxicity." Integrative Cancer Therapies 4(2): 110-30.
  15. Greenlee, H., J. Shaw, et al. Lack of Effect of Coenzyme Q10 on Doxorubicin Cytotoxicity in Breast Cancer Cell Cultures. Integrative Cancer Therapies 2012; 11(3): 243-250.
  16. Werbach M R. Nutritional strategies for treating chronic fatigue syndrome. Alternative Medicine Review. 2000; 5(2):93-108
  17. Jellin, JM., (Ed). Natural Medicines Comprehensive Database. 2003; Stockton, California: Therapeutic Research Faculty.
  18. Damkier A, Jensen AB, Rose C. Use of Q10 in cancer patients. Ugeskr Laeger. 1994, 7;156(6):813-8.
  19. Sachdanandam P. Antiangiogenic and hypolipidemic activity of coenzyme Q10 supplementation to breast cancer patients undergoing Tamoxifen therapy. Biofactors. 2008;32(1-4):151-9.
  20. Rusciani L, Proietti I, Paradisi A, Rusciani A, Guerriero G, Mammone A, et al. Recombinant interferon alpha-2b and coenzyme Q10 as a postsurgical adjuvant therapy for melanoma: a 3-year trial with recombinant interferon-alpha and 5-year follow-up. Melanoma Res. 2007 Jun;17(3):177-8
  21. Ernst E, Pittler MH, Wider B, Boddy K. Oxford Handbook of Complementary Medicine. Oxford University Press (2008). ISBN 978-0-19-920677-3
  22. Molassiotis A, Scott JA, Kearney N, Pud D, Magri M, Selvekerova S, Bruyns I, Fernadez-Ortega P, Panteli V, Margulies A, Gudmundsdottir G, Milovics L, Ozden G, Platin N, Patiraki E. Complementary and alternative medicine use in breast cancer patients in Europe. Support Care Cancer. 2006 Mar;14(3):260-7.
  23. van Dalen EC, Caron HN, Dickinson HO, Kremer LC, van Dalen EC, Caron HN et al. Cardioprotective interventions for cancer patients receiving anthracyclines.[Update of Cochrane Database Syst Rev. 2008;(2):CD003917; PMID: 18425895]. Cochrane Database of Systematic Reviews 2011; 6:CD003917.
  24. Roffe, L, Schmidt, K, & Ernst, E. Efficacy of coenzyme Q10 for improved tolerability of cancer treatments: a systematic review. Journal of Clinical Oncology. 2004; 1;22 (21): 4418-24.
  25. Bryant, J., J. Picot, et al. (2007)"Cardioprotection against the toxic effects of anthracyclines given to children with cancer: a systematic review." Health Technology Assessment (Winchester, England) 11(27): ii
  26. Nicolson GL, Conklin KA. Reversing mitochondrial dysfunction, fatigue and the adverse effects of chemotherapy of metastatic disease by molecular replacement therapy. Clin Exp Metastasis. 2008;25(2):161-9.
  27. Shinozawa, S, Gomita, Y, & Araki, Y. Protective effects of various drugs on adriamycin (doxorubicin)-induced toxicity and microsomal lipid peroxidation in mice and rats. Biological and Pharmaceutical Bulletin. 1993; 16 (11): 1114-7.
  28. Chandran K, Aggarwal D, Migrino RQ, Joseph J, McAllister D, Konorev EA et al. Doxorubicin inactivates myocardial cytochrome c oxidase in rats: cardioprotection by Mito-Q. Biophysical Journal 2009; 96(4):1388-1398
  29. Shaeffer, J, El-Mahdi. AM, & Nichols, RK. Coenzyme Q10 and adriamycin toxicity in mice. Research Communication in Chemical Patholology and Pharmacology. 1980; 29 (2): 309-15.
  30. Lund, EL, Quistorff, B, Spang-Thomsen, M, & Kristjansen, PE. Effect of radiation therapy on small-cell lung cancer is reduced by ubiquinone intake. Folia Microbiologica (Praha). 1998; 43 (5): 505-6.
  31. Fouad AA, Al-Sultan AI, Refaie SM, Yacoubi MT, Fouad AA, Al-Sultan AI et al. Coenzyme Q10 treatment ameliorates acute cisplatin nephrotoxicity in mice. Toxicology 2010; 274(1-3):49-56.
  32. Hidaka, J, Fujii, K, et al. (2008) Safety assessment of Coenzyme Q10 (CoQ10). Biofactors 32(1-4): 499-508.
  33. Villalba JM, Parrado C, Santos-Gonzalez M, Alcain FJ, Villalba JM, Parrado C et al. Therapeutic use of coenzyme Q10 and coenzyme Q10-related compounds and formulations. [Review] [211 refs]. Expert Opinion on Investigational Drugs 2010; 19(4):535-554.
  34. Baggio, E, Gandini, R, Plancher, AC, Passeri, M, & Carmosino, G. Italian multicenter study on the safety and efficacy of coenzyme Q10 as adjunctive therapy in heart failure. CoQ10 Drug Surveillance Investigators. Molecular Aspects of Medicine. 1994; 15 (Suppl): s287-94.
  35. Feigin, A, Kieburtz, K, Como, P, Hickey, C, Claude, K, Abwender, D, Zimmerman, C, Steinberg, K, & Shoulson, I. Assessment of coenzyme Q10 tolerability in Huntington's disease. Movement Disorders. 1996; 11 (3): 321-3.
  36. Pepping, J. Coenzyme Q10. American Journal of Health System-Pharmacy. 1999; 56 (6): 519-21.
  37. Ernst E, Pittler MH, Wider B, Boddy K. (Eds). The Desktop Guide to Complementary and Alternative Medicine. An Evidence-Based Approach. Edinburgh: Mosby, 2006.
  38. Engelsen J, Nielsen JD, Hansen KF. Effect of Coenzyme Q10 and Ginkgo biloba on warfarin dosage in patients on long-term warfarin treatment. A randomized, double-blind, placebo-controlled cross-over trial. Ugeskr Laeger. 2003, 28 ;165(18):1868-71.
  39. Borek, C. Dietary antioxidants and human cancer. Integrative Cancer Therapies. 2004; 3 (4), 333-341
  40. Kaikkonen, J, Nyyssonen, K, Tuomainen, TP, Ristonmaa, U, & Salonen, JT. Determinants of plasma coenzyme Q10 in humans. FEBS Letters. 1999; 443 (2): 163-6.
  41. Overvad, K, Diamant, B, Holm, L, Holmer, G, Mortensen, SA, & Stender, S. Coenzyme Q10 in health and disease. European Journal of Clinical Nutrition. 1999; 53 (10): 764-70.
  42. ConsumerLab: Product review: Coenzyme Q10.. [online]. 20011 [cited 2012 Oct 22]. Available from: URL http://www.consumerlab.com/results/coq10.asp
  43. Folkers, K, Porter, TH, Bertino, JR, & Moroson, B. Inhibition of two human tumor cell lines by antimetabolites of coenzyme Q10. Research Communication in Chemical Pathology and Pharmacology. 1978; 19 (3): 485-90.