Coenzyme Q10 (CoQ10), also called ubiquinone or ubidecarenone, is a fat-soluble compound that the human body makes itself. Cells use it in mitochondria, the structures that turn food into usable energy, and it also works as an antioxidant. The highest levels are found in the heart, liver, kidneys and pancreas (NCCIH).
In the US, CoQ10 is sold as a dietary supplement, not as an approved drug. It is marketed for endurance and recovery, and it has been studied in heart failure, statin-related muscle pain, migraine and Parkinson disease. The most important fact: the best evidence is in heart failure, where one 420-patient trial found fewer major cardiac events. For exercise performance, meta-analyses find at most small and inconsistent effects.
This page summarizes what clinical trials, meta-analyses and US government health agencies report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Class | Endogenous benzoquinone; dietary supplement |
| Other names | Ubiquinone, ubidecarenone, vitamin Q10; reduced form is ubiquinol |
| Formula / weight | C₅₉H₉₀O₄, 863.3 g/mol (ubiquinone) |
| Route | Oral (capsules, softgels, solubilized liquids) |
| Doses in trials | Usually 90–390 mg/day; 300 mg/day in the main heart failure trial; up to 2,400 mg/day in a Parkinson disease trial |
| Half-life | ≈33 h after a single 100 mg oral dose; peak at ≈6 h |
| Key mechanism | Carries electrons in the mitochondrial energy chain; also acts as an antioxidant |
| US status | Dietary supplement; not FDA-approved for any medical condition |
| WADA status | Not named on the 2026 Prohibited List |
What it is
The name describes the structure. “Q” refers to the quinone ring, a benzoquinone, and “10” to the chain of 10 isoprene units attached to it (NCI PDQ). The long chain makes the molecule very fat-soluble and large (863.3 g/mol), which limits how well it is absorbed (PubChem; Bhagavan & Chopra, Free Radic Res 2006).
CoQ10 was first isolated in 1957, and its structure was worked out in 1958 (NCI PDQ). It exists in two forms that switch back and forth in the body:
| Form | Chemistry | Notes |
|---|---|---|
| Ubiquinone | Oxidized form, C₅₉H₉₀O₄, 863.3 g/mol | Standard supplement form |
| Ubiquinol | Reduced form, C₅₉H₉₂O₄, 865.4 g/mol | Sold as a separate supplement product |
Its two main jobs are:
- Energy production. It shuttles electrons in the mitochondrial respiratory chain and is a cofactor for mitochondrial enzymes (Al Saadi et al., Cochrane 2021).
- Antioxidant defense. It helps protect cell components such as DNA and lipids from damage by free radicals (NCI PDQ).
Low heart muscle CoQ10 has been linked to more severe heart failure. This was the rationale for testing it as an add-on treatment (Mortensen et al., JACC Heart Fail 2014).
How it works in the body
Absorption of oral CoQ10 is slow and limited because of its size and fat solubility. Solubilized formulations are better absorbed, and taking it with fat helps (Bhagavan & Chopra, Free Radic Res 2006; NCI PDQ).
The most cited kinetic study gave 100 mg of deuterium-labeled CoQ10 by mouth to 16 healthy men (Tomono et al., 1986):
| Parameter | Value |
|---|---|
| Peak plasma level | 1.004 ± 0.370 µg/mL |
| Time to peak | 6.5 ± 1.5 h |
| Terminal elimination half-life | 33.19 ± 5.32 h |
| Second peak | At ≈24 h in most subjects |
The authors explained the second peak by uptake into the liver, followed by release back into the blood in VLDL particles (a type of lipoprotein). Normal plasma CoQ10 in healthy adults ranges from 0.40 to 1.91 µmol/L. Plasma levels rise with the dose, but only up to a point (Bhagavan & Chopra, Free Radic Res 2006).
Ubiquinone vs ubiquinol
Ubiquinol is often marketed as the “better absorbed” form. A randomized three-way crossover study in 21 healthy adults aged 65–74 compared single 100 mg doses of three products over 48 hours (Pravst et al., Nutrients 2020):
| Formulation | Total CoQ10 exposure vs standard ubiquinone capsules |
|---|---|
| Water-soluble CoQ10 syrup | 2.4-fold higher (95% CI 1.3–4.5) |
| Ubiquinol capsules | 1.7-fold higher, not significant (95% CI 0.9–3.1) |
Whatever form was swallowed, CoQ10 appeared in the blood mostly as ubiquinol. The formulation (how well the product is solubilized) mattered more than the redox form in this study.
Regulatory status
- United States. CoQ10 is regulated as a dietary supplement. Supplements do not need FDA premarket approval unless they make disease claims, and the FDA has not approved CoQ10 for cancer or any other medical condition (NCI PDQ).
- Sport. CoQ10 is not named anywhere on the WADA 2026 Prohibited List.
What the research shows
Heart failure
Q-SYMBIO was a randomized, double-blind, multicenter trial in 420 patients with moderate to severe chronic heart failure (Mortensen et al., JACC Heart Fail 2014). Patients received CoQ10 100 mg three times daily or placebo for 2 years, on top of standard therapy.
| Outcome at 2 years | CoQ10 | Placebo | Result |
|---|---|---|---|
| Major adverse cardiovascular events (primary endpoint) | 15% | 26% | HR 0.50 (95% CI 0.32–0.80); p = 0.003 |
| Cardiovascular death | 9% | 16% | p = 0.026 |
| Death from any cause | 10% | 18% | p = 0.018 |
| Hospital stays for heart failure | — | — | Lower with CoQ10 (p = 0.033) |
The short-term endpoints at 16 weeks did not change: symptom class, 6-minute walk distance and NT-proBNP (a blood marker of heart strain).
A 2021 Cochrane review pooled 11 trials with 1,573 participants (Al Saadi et al., Cochrane 2021). It rated the evidence as moderate quality that CoQ10 probably reduces all-cause death (RR 0.58, 95% CI 0.35–0.95) and heart failure hospitalization (RR 0.62, 95% CI 0.49–0.78). The mortality estimate rests on Q-SYMBIO alone. Effects on ejection fraction and exercise capacity were very uncertain, and the reviewers concluded there is “no convincing evidence to support or refute” its use.
Statin-related muscle symptoms
Statins lower blood CoQ10. A meta-analysis of placebo-controlled trials found an average fall of 0.44 µmol/L (95% CI 0.37–0.52), seen with atorvastatin, simvastatin, rosuvastatin and pravastatin alike (Banach et al., Pharmacol Res 2015). Whether this causes statin muscle pain, and whether CoQ10 relieves it, is disputed:
| Meta-analysis | Trials / patients | Muscle pain | Creatine kinase |
|---|---|---|---|
| Banach et al., Mayo Clin Proc 2015 | 6 / 302 | No significant effect (SMD −0.53, 95% CI −1.33 to 0.28) | No significant change |
| Qu et al., J Am Heart Assoc 2018 | 12 / 575 | Reduced (WMD −1.60, 95% CI −1.75 to −1.44) | No significant change |
| Kovacic et al., J Nutr Sci 2025 | 7 / 389 | Reduced (WMD −0.96, 95% CI −1.88 to −0.03) | Not assessed |
The trials were small and short (30–90 days in the 2025 review) and used 100–600 mg/day. NCCIH’s summary states that the overall evidence does not support CoQ10 for statin muscle pain (NCCIH).
Exercise performance and recovery
This is the main reason CoQ10 appears in sports nutrition. The data are weaker than the marketing suggests.
- Performance. A 2025 meta-analysis of 24 randomized trials in healthy adults found that CoQ10 reliably raised blood levels, but effects on performance were small and inconsistent (Deng et al., Br J Nutr 2025). Single doses did nothing. A small benefit of longer use, mostly for aerobic endurance, became unstable once outlier studies were removed. Strength and anaerobic outcomes barely changed, and certainty was rated very low to low.
- Muscle damage markers. A 2024 meta-analysis of 28 trials (830 participants) found lower blood markers of exercise-induced muscle damage and oxidative stress (Talebi et al., Clin Nutr ESPEN 2024).
| Marker (Talebi 2024) | Change with CoQ10 (95% CI) |
|---|---|
| Creatine kinase (CK) | −50.64 IU/L (−74.75 to −26.53) |
| Lactate dehydrogenase (LDH) | −52.10 IU/L (−74.01 to −30.19) |
| Myoglobin | −21.77 ng/mL (−32.59 to −10.94) |
| Malondialdehyde (lipid damage marker) | −0.73 µmol/L (−1.26 to −0.20) |
| Total antioxidant capacity | No significant change |
Lower blood markers are not the same as faster recovery of strength or better results. The authors also noted that most trials were done in Asia, which limits how far the findings generalize.
Blood pressure
A Cochrane review limited to well-designed trials in primary hypertension pooled 2 trials with 50 participants. CoQ10 did not significantly change systolic (−3.68 mm Hg, 95% CI −8.86 to 1.49) or diastolic pressure (−2.03 mm Hg, 95% CI −4.86 to 0.81) (Ho et al., Cochrane 2016). The reviewers concluded it has no clinically significant effect on blood pressure.
Migraine
In a randomized, double-blind trial in 42 people with migraine, CoQ10 100 mg three times daily beat placebo in the third month. The share of patients whose attacks halved was 47.6% vs 14.4% (Sándor et al., Neurology 2005). The American Academy of Neurology and American Headache Society guideline rates CoQ10 as “possibly effective” (Level C) for preventing migraine (Holland et al., Neurology 2012).
Parkinson disease
The QE3 phase III trial randomized 600 people with early Parkinson disease to placebo, 1,200 mg/day or 2,400 mg/day of CoQ10 for up to 16 months (QE3 Investigators, JAMA Neurol 2014). It was stopped early for futility. Both CoQ10 groups showed slight trends toward worse scores than placebo (not significant), but even these high doses were well tolerated.
Side effects and risks
General tolerability
CoQ10 has a good safety record in trials:
- No serious toxicity has been reported. Doses of 100 mg/day or more have caused mild insomnia in some people (NCI PDQ).
- Gut symptoms such as nausea, upper abdominal pain and heartburn have been reported, along with rash, dizziness, headache and fatigue (NCI PDQ).
- Liver enzyme rises have been seen with 300 mg/day over long periods, without reported liver toxicity (NCI PDQ).
A formal risk assessment found that gastrointestinal complaints were no more common at 1,200 mg/day than at 60 mg/day. It set the observed safe level at 1,200 mg/day; higher doses have been tested, but the data above that level were too limited for a firm conclusion (Hathcock & Shao, Regul Toxicol Pharmacol 2006). Ubiquinol at up to 300 mg/day for 4 weeks caused no relevant changes in lab tests, vital signs or ECG in healthy volunteers (Hosoe et al., Regul Toxicol Pharmacol 2007).
Interactions
- Warfarin. Case reports described a weaker warfarin effect, and NCCIH lists warfarin as a possible interaction (NCCIH). In a randomized, double-blind crossover trial in 24 patients on stable warfarin, CoQ10 100 mg/day for 4 weeks did not change the INR or the warfarin dose (Engelsen et al., Ugeskr Laeger 2003). Higher doses were not tested.
- Diabetes drugs. CoQ10 may lower insulin needs in people with diabetes, and NCCIH notes a possible interaction with insulin (NCI PDQ; NCCIH).
- Cancer treatment. NCCIH notes that CoQ10 may not be compatible with some cancer treatments. In mice, it reduced the effect of radiation on implanted human lung tumors (NCI PDQ).
- Statins and some other drugs lower blood CoQ10 (see above).
Product quality
Because supplements do not go through premarket review, the amount of ingredient can vary from lot to lot, and there is no guarantee a product contains what its label claims (NCI PDQ). Formulation also changes how much is absorbed (see the bioavailability table above).
Key takeaways
- A natural mitochondrial cofactor sold as a supplement. The body makes CoQ10 for energy production and antioxidant defense; in the US it is a dietary supplement, not an approved drug.
- Slow absorption, long half-life. Blood levels peak at about 6 hours and the half-life is about 33 hours; solubilized products are absorbed better than standard capsules.
- Best evidence is in heart failure. One 420-patient trial at 300 mg/day halved major cardiac events over 2 years, but that single trial drives most of the benefit seen in the Cochrane review.
- Small or no effect for athletes. CoQ10 lowers some muscle damage markers, but meta-analyses find no consistent improvement in endurance, strength or power.
- Mixed or negative elsewhere. Statin muscle pain results conflict; no clinically meaningful blood pressure effect; no benefit in early Parkinson disease; “possibly effective” for migraine.
- Well tolerated. Side effects are mostly mild gut upset and insomnia, with strong safety data up to 1,200 mg/day; check for interactions with warfarin, insulin and cancer treatment.
Sources
- National Center for Complementary and Integrative Health. Coenzyme Q10. Last updated January 2019. NCCIH.
- PDQ Integrative, Alternative, and Complementary Therapies Editorial Board. Coenzyme Q10 (PDQ)–Health Professional Version. National Cancer Institute. Updated October 31, 2024. NCI.
- National Center for Biotechnology Information. PubChem Compound Summary for CID 5281915, Coenzyme Q10. PubChem.
- Bhagavan HN, Chopra RK. Coenzyme Q10: absorption, tissue uptake, metabolism and pharmacokinetics. Free Radic Res. 2006;40(5):445–453. PubMed.
- Tomono Y, Hasegawa J, Seki T, et al. Pharmacokinetic study of deuterium-labelled coenzyme Q10 in man. Int J Clin Pharmacol Ther Toxicol. 1986;24(10):536–541. PubMed.
- Pravst I, Rodríguez Aguilera JC, Cortes Rodriguez AB, et al. Comparative bioavailability of different coenzyme Q10 formulations in healthy elderly individuals. Nutrients. 2020;12(3):784. PubMed.
- Mortensen SA, Rosenfeldt F, Kumar A, et al. 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. PubMed.
- Al Saadi T, Assaf Y, Farwati M, et al. Coenzyme Q10 for heart failure. Cochrane Database Syst Rev. 2021;(2):CD008684. PubMed.
- Banach M, Serban C, Ursoniu S, et al. Statin therapy and plasma coenzyme Q10 concentrations—a systematic review and meta-analysis of placebo-controlled trials. Pharmacol Res. 2015;99:329–336. PubMed.
- Banach M, Serban C, Sahebkar A, et al. Effects of coenzyme Q10 on statin-induced myopathy: a meta-analysis of randomized controlled trials. Mayo Clin Proc. 2015;90(1):24–34. PubMed.
- Qu H, Guo M, Chai H, et al. Effects of coenzyme Q10 on statin-induced myopathy: an updated meta-analysis of randomized controlled trials. J Am Heart Assoc. 2018;7(19):e009835. PubMed.
- Kovacic S, Habicht SD, Eckert GP. Effects of coenzyme Q10 supplementation on myopathy in statin-treated patients: a systematic review and meta-analysis. J Nutr Sci. 2025;14:e72. PubMed.
- Deng H, Song T, Yin M, et al. Coenzyme Q10 supplementation increases blood concentrations but shows limited and inconsistent effects on exercise performance: a systematic review and meta-analysis. Br J Nutr. Published online December 29, 2025:1–21. PubMed.
- Talebi S, Pourgharib Shahi MH, Zeraattalab-Motlagh S, et al. The effects of coenzyme Q10 supplementation on biomarkers of exercise-induced muscle damage, physical performance, and oxidative stress: a GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials. Clin Nutr ESPEN. 2024;60:122–134. PubMed.
- Ho MJ, Li EC, Wright JM. Blood pressure lowering efficacy of coenzyme Q10 for primary hypertension. Cochrane Database Syst Rev. 2016;(3):CD007435. PubMed.
- 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. PubMed.
- Holland S, Silberstein SD, Freitag F, et al. Evidence-based guideline update: NSAIDs and other complementary treatments for episodic migraine prevention in adults: report of the Quality Standards Subcommittee of the American Academy of Neurology and the American Headache Society. Neurology. 2012;78(17):1346–1353. PubMed.
- Parkinson Study Group QE3 Investigators; Beal MF, Oakes D, Shoulson I, et al. A randomized clinical trial of high-dosage coenzyme Q10 in early Parkinson disease: no evidence of benefit. JAMA Neurol. 2014;71(5):543–552. PubMed.
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- Hosoe K, Kitano M, Kishida H, et al. Study on safety and bioavailability of ubiquinol (Kaneka QH) after single and 4-week multiple oral administration to healthy volunteers. Regul Toxicol Pharmacol. 2007;47(1):19–28. PubMed.
- 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;165(18):1868–1871. PubMed.
- World Anti-Doping Agency. The 2026 Prohibited List. WADA 2026 Prohibited List.