Also known as CoQ10, Ubiquinone, Ubiquinol
Fat-soluble compound essential to mitochondrial ATP production and antioxidant defence; levels decline with age and statin use, so supplementation is studied for statin-associated muscle symptoms and cardiovascular support.
Reported side effects:Insomnia (mild)Mild digestive upsetsAdverse events (corpus row; Cochrane review of CoQ10 for heart failure)
Be careful if: some medical situations, pregnant, breastfeeding
Ask first if you take: blood thinners (anticoagulants or antiplatelets), diabetes medicines, including insulin, chemotherapy
Suspect a side effect? Report it to the MHRA Yellow Card scheme ↗
We link to relevant studies and leave interpretation to you and your healthcare professional.
The large figures are what the studies reported for each thing they measured. Open a card for every result.
Colour keyReported a benefitNo clear benefitUnclearPossible harmAmber is for highlights, such as where the most research is. It never means a result was good.
Also measured alongside: Short-burst exercise performance (reported a benefit); Antioxidant activity (reported a benefit); Liver enzymes (reported a benefit); and 2 more.
Every resultAlso measured alongside: Exercise capacity (unclear).
2 more measuresWhat sources report about side effects, who should be careful, and medicines to ask about first.
| Reported effect | How often | Basis | Sources |
|---|---|---|---|
| Insomnia (mild) | unknown | Listed by NIH ODS fact sheets | NIH NCCIH fact sheet: Coenzyme Q10 |
| Mild digestive upsets | unknown | Listed by NIH ODS fact sheets | NIH NCCIH fact sheet: Coenzyme Q10 |
| Adverse events (corpus row; Cochrane review of CoQ10 for heart failure) | unknown | Listed by PubMed corpus rows (PubMed 35608922) | Cochrane review, CoQ10 for heart failure, PMID 35608922 |
| Applies to | What sources say | Sources |
|---|---|---|
| some medical situations | NCCIH reports few side effects from CoQ10 supplements, including at 100 mg a day or less for up to 30 months in studies; long-term safety above that dose has not been established. | NIH NCCIH fact sheet: Coenzyme Q10 |
| pregnant | Pregnancy not addressed in the retrieved sources (NCCIH fact sheet does not cover it; no BNF/NHS entry exists). Not advised in pregnancy without medical advice. | NIH NCCIH fact sheet: Coenzyme Q10 |
| breastfeeding | Breastfeeding not addressed in the retrieved sources (NCCIH fact sheet does not cover it; no BNF/NHS entry exists). Not advised while breastfeeding without medical advice. | NIH NCCIH fact sheet: Coenzyme Q10 |
| Severity | Medicine | Sources |
|---|---|---|
| caution | blood thinners (anticoagulants or antiplatelets) — CoQ10 may interact with warfarin (NCCIH; direction of effect not stated). | NIH NCCIH fact sheet: Coenzyme Q10 |
| caution | diabetes medicines, including insulin — CoQ10 may interact with insulin and diabetes medicines (NCCIH); people on insulin should not take CoQ10 without talking to a clinician. | NIH NCCIH fact sheet: Coenzyme Q10 |
| ask first | chemotherapy — CoQ10 may not be compatible with some types of cancer treatment; do not combine without clinical advice (NCCIH). | NIH NCCIH fact sheet: Coenzyme Q10 |
Audited published research for Coenzyme Q10 by condition. Drill into a pair page for the full breakdown.
What this means: Bars count reported findings, not treatment effectiveness or certainty.
One study may report several findings or appear in more than one pairing. Counts do not show the size of an effect. Comparable numerical estimates are not established for this summary.
| Compound and condition | Findings (count) | Studies (count) | Reported results (finding counts) | How sure? |
|---|---|---|---|---|
| Fatigue | 6 | 2 | Benefit: 6; no benefit: 0; harm: 0; unclear: 0; not recorded / unrecognised: 0 | Not formally graded |
| Heart Health | 7 | 1 | Benefit: 3; no benefit: 0; harm: 0; unclear: 4; not recorded / unrecognised: 0 | Not formally graded |
Where people report using it and what trials suggest
Common claims the trials do not support
Mitochondrial coenzyme with strongest signals in heart-failure adjunct and migraine prevention; famous for its null statin-myalgia trials.
Evidence grades reflect study quality and consistency, not marketing claims.
Ordered by strength of evidence, then result direction.
01Dietary Supplementation for Fatigue Symptoms in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)-A Systematic ReviewDorczok MC, et al. · Nutrients · 2025PMID 39940333 ↗02Coenzyme Q10 supplementation in rheumatic diseases: A systematic reviewFreire de Carvalho J, et al. · Clinical nutrition ESPEN · 2024PMID 38220408 ↗03Evaluating the efficacy of ubiquinol in heart failure patients: a systematic review and meta-analysisQazi SU, et al. · Future cardiology · 2024PMID 39049769 ↗04Drug therapy versus placebo or usual care for comatose survivors of cardiac arrest; a systematic review with meta-analysisMcGuigan PJ, et al. · Resuscitation · 2024PMID 39547562 ↗05Interventions for the management of long covid (post-covid condition): living systematic reviewZeraatkar D, et al. · BMJ (Clinical research ed.) · 2024PMID 39603702 ↗06Coenzyme Q10 Supplementation in Athletes: A Systematic ReviewFernandes MSS, et al. · Nutrients · 2023PMID 37764774 ↗Reported results grouped by condition. Values and units are preserved as recorded; missing information is not estimated.
How to read this table
Reported direction, numerical results and study design are separate. Certainty has not been formally graded in this table.
| What was measured | Reported findings | Result and units | Reported sample and duration | Study / source |
|---|---|---|---|---|
| anaerobic performance | Anaerobic performance increased with CoQ10 supplementation compared to baseline in athletes.Benefit seen | Not reported Recorded unit: Not reported | Sample (as reported): Not reported Follow-up: Not reported | Systematic review · 2023 Study detailsCoenzyme Q10 Supplementation in Athletes: A Systematic Review. Systematic Review |
| antioxidant activity | Antioxidant activity increased with CoQ10 supplementation compared to baseline in athletes.Benefit seen | Not reported Recorded unit: Not reported | Sample (as reported): Not reported Follow-up: Not reported | Systematic review · 2023 Study detailsCoenzyme Q10 Supplementation in Athletes: A Systematic Review. Systematic Review |
| fatigue indicators (Creatine Kinase) | Fatigue indicators decreased with CoQ10 supplementation compared to baseline in athletes.Benefit seen | Not reported Recorded unit: Not reported | Sample (as reported): Not reported Follow-up: Not reported | Systematic review · 2023 Study detailsCoenzyme Q10 Supplementation in Athletes: A Systematic Review. Systematic Review |
| liver damage markers (ALT, AST, γGT) | Liver damage markers decreased with CoQ10 supplementation compared to baseline in athletes.Benefit seen | Not reported Recorded unit: Not reported | Sample (as reported): Not reported Follow-up: Not reported | Systematic review · 2023 Study detailsCoenzyme Q10 Supplementation in Athletes: A Systematic Review. Systematic Review |
| oxidative stress markers | Oxidative stress markers decreased with CoQ10 supplementation compared to baseline in athletes.Benefit seen | Not reported Recorded unit: Not reported | Sample (as reported): Not reported Follow-up: Not reported | Systematic review · 2023 Study detailsCoenzyme Q10 Supplementation in Athletes: A Systematic Review. Systematic Review |
| fatigue scores | CoQ10 reduced fatigue scores by Hedges' g -0.398 vs placebo in 1,126 participants. (95% confidence interval = -0.641 to -0.155, p = 0.001)Benefit seen | -0.398 Hedges' g Recorded unit: Not reported | Sample (as reported): 1,126 Follow-up: Not reported | Systematic review · 2022 Study detailsEffectiveness of Coenzyme Q10 Supplementation for Reducing Fatigue: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Systematic Review |
| What was measured | Reported findings | Result and units | Reported sample and duration | Study / source |
|---|---|---|---|---|
| adverse events | Results for adverse events risk were inconclusive with RR 0.70 vs control in 568 participants. (95% CI 0.45 to 1.10)Unclear | 0.70 RR Recorded unit: Not reported | Sample (as reported): 568 Follow-up: Not reported | Meta-analysis · 2021 Study detailsCoenzyme Q10 for heart failure. Meta-Analysis |
| all-cause mortality | Coenzyme Q10 probably reduced all-cause mortality risk by RR 0.58 vs control in 420 participants. (95% CI 0.35 to 0.95)Benefit seen | 0.58 RR Recorded unit: Not reported | Sample (as reported): 420 Follow-up: Not reported | Meta-analysis · 2021 Study detailsCoenzyme Q10 for heart failure. Meta-Analysis |
| exercise capacity | Results for exercise capacity were inconclusive with MD 48.23 vs control in 91 participants. (95% CI -24.75 to 121.20)Unclear | 48.23 MD Recorded unit: Not reported | Sample (as reported): 91 Follow-up: Not reported | Meta-analysis · 2021 Study detailsCoenzyme Q10 for heart failure. Meta-Analysis |
| hospitalisation related to heart failure | Coenzyme Q10 probably reduced heart failure hospitalisation risk by RR 0.62 vs control in 1061 participants. (95% CI 0.49 to 0.78)Benefit seen | 0.62 RR Recorded unit: Not reported | Sample (as reported): 1061 Follow-up: Not reported | Meta-analysis · 2021 Study detailsCoenzyme Q10 for heart failure. Meta-Analysis |
| left ventricular ejection fraction | Coenzyme Q10 may improve left ventricular ejection fraction by MD 1.77 vs control in 650 participants. (95% CI 0.09 to 3.44)Benefit seen | 1.77 MD Recorded unit: Not reported | Sample (as reported): 650 Follow-up: Not reported | Meta-analysis · 2021 Study detailsCoenzyme Q10 for heart failure. Meta-Analysis |
| myocardial infarction | Results for myocardial infarction risk were inconclusive with RR 1.62 vs control in 420 participants. (95% CI 0.27 to 9.59)Unclear | 1.62 RR Recorded unit: Not reported | Sample (as reported): 420 Follow-up: Not reported | Meta-analysis · 2021 Study detailsCoenzyme Q10 for heart failure. Meta-Analysis |
| stroke | Results for stroke risk were inconclusive with RR 0.18 vs control in 420 participants. (95% CI 0.02 to 1.48)Unclear | 0.18 RR Recorded unit: Not reported | Sample (as reported): 420 Follow-up: Not reported | Meta-analysis · 2021 Study detailsCoenzyme Q10 for heart failure. Meta-Analysis |
Associated conditions and community-reported outcomes, wrapped together on one page. Aggregates appear only once enough reports arrive.
How this compound is sold in the UK, and where our readers typically find it.
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