Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

CoQ-10 ZEN Ingredients & Drug Interactions

by Natural Rhythm

CoQ-10 ZEN label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking CoQ-10 ZEN against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

CoQ-10 ZEN is a dietary supplement by Natural Rhythm with 3 active ingredients. Its ingredients are commonly taken for anxiety and stress, relaxation and calm, sleep support.Based on those ingredients, 608 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-Theanine, Coenzyme Q10, L-Carnitine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against CoQ-10 ZEN by Natural Rhythm

Ask about any prescription or over-the-counter medication and we check it for interactions with CoQ-10 ZEN by Natural Rhythm — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of CoQ-10 ZEN by Natural Rhythm

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 12, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

CoQ-10 ZEN contains three active ingredients. L-theanine is an amino acid that may support cognitive function.

Coenzyme Q10 (CoQ10) is a natural compound involved in energy production in cells and is used in heart and migraine health. L-carnitine is another amino acid that helps transport fatty acids for energy.

The product also contains inactive ingredients—hypromellose, microcrystalline cellulose, and vegetarian leucine—which serve as capsule material and binders.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Heart health, energy, stress and sleep support.
  • We looked for evidence on: Cardiovascular disease (CVD), Congestive heart failure (CHF), Coronary heart disease (CHD), Arrhythmia, Atrial fibrillation, Angina — and 4 related terms.
  • The strongest evidence on file: Coenzyme Q10 is rated "Possibly Effective" for Congestive heart failure (CHF) (Natural Medicines).
  • Also on file: L-carnitine is rated "Possibly Effective" for Angina, Congestive heart failure (CHF), Hyperlipidemia.
  • Also on file: Coenzyme Q10 is rated "Possibly Ineffective" for Chemotherapy-related fatigue.

L-theanine is possibly effective for cognitive function, but evidence is insufficient for age-related cognitive decline, Alzheimer disease, or anxiety disorders like GAD and OCD. Coenzyme Q10 is likely effective for CoQ10 deficiency itself and possibly effective for fibromyalgia, migraine headaches, heart failure, and diabetic nerve pain.

L-carnitine is effective for L-carnitine deficiency and possibly effective for high cholesterol, heart failure, and chest pain (angina).

The evidence, ingredient by ingredient Theanine Coenzyme Q10 L-carnitine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

All three ingredients are generally well tolerated at typical doses. L-theanine may cause headaches, drowsiness, or increased dream activity; long-term safety isn't well studied.

CoQ10 is generally well tolerated, with most adverse effects being gastrointestinal (nausea, diarrhea, heartburn) occurring in less than 1% of users. L-carnitine may cause stomach upset and a fishy body odor at higher doses; seizures have been reported rarely.

Pregnancy: L-theanine has insufficient safety data and should be avoided in pregnancy. CoQ10 also lacks reliable safety data in pregnancy.

L-carnitine's pregnancy safety is not well studied. Breastfeeding: L-theanine and L-carnitine lack sufficient safety data; use only with medical advice.

CoQ10 is possibly safe while breastfeeding but caution is advised—talk with your doctor.

Side effects, ingredient by ingredient Theanine Coenzyme Q10 L-carnitine

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 3 of the 3 matched ingredients can interact with medications — Coenzyme Q10, L-carnitine, Theanine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 608 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking CoQ-10 ZEN, double-check any blood thinners you take (warfarin and acenocoumarol specifically): L-carnitine may increase their effect while CoQ10 may decrease it. Confirm your blood pressure medications with us too, since both L-theanine and CoQ10 might lower blood pressure further.

If you take thyroid hormone replacement, L-carnitine could reduce its effectiveness. Tell us about any chemotherapy drugs as well, since CoQ10 may interfere with certain types.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

CoQ-10 ZEN may appeal to you if you're interested in heart health, energy support, or cognitive function, but the three-ingredient combination carries multiple drug interactions—especially concerning if you take blood thinners, blood pressure medications, thyroid hormones, or chemotherapy. Check your exact medications with the tool on this page before starting, and talk with your pharmacist or doctor, particularly if you're pregnant, breastfeeding, or on any prescription.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 16, 2022.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about CoQ-10 ZEN, straight from the product label.

Brand Natural Rhythm
Barcode (UPC) 764804317459
Net contents 30 Capsule(s)
Market status On market
Date entered into DSLD Jun 16, 2022
DSLD ID 271240
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses All Other, Qualified Health, Structure/Function
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for CoQ-10 ZEN by Natural Rhythm, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Vegetable Capsule(s)
Maximum serving Sizes:
1 Vegetable Capsule(s)
Servings per container
30
UPC/BARCODE
764804317459
IngredientAmount% DV
L-Theanine15 mg--
Coenzyme Q10100 mg--
L-Carnitine125 mg--

Other ingredients: Hypromellose, Microcrystalline Cellulose, vegetarian Leucine

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Formula

CoQ-10 for Your Heart CoQ-10 supports cardiovascular functions and is an essential catalyst for the creation of energy at the cellular level. Coenzyme Q10 is an important free-radical fighter and is recommended to support proper heart, liver and gum tissue functions.

L-Carnitine for Your Mind & Muscles L-Carnitine boosts physical and mental energy and endurance, reduces fatigue and muscle loss, and enhances cognitive function.

L-Theanine for Your Stress & Anxiety L-Theanine is an amino acid found naturally in green tea and may help alleviate, improve sleep, and reduce stress.

CoQ10 + L Carnitine + L-Theanine

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Seals/Symbols

GMP Good Manufacturing Practice Quality Product

Formulation

Pure. Max absorption. Easy on stomach.

To support cardiovascular functions, and help reduce stress & anxiety

Vegetarian

Gluten free

Non-GMO ingredients

Color of this product may vary due to color variations of the natural ingredients.

No Gluten, soy, milk, preservatives, or animal products. Formulated without eggs, fish, shellfish, tree nuts, peanuts, or wheat. Yay!!

FDA Statement of Identity

A Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take 1 capsule daily with a meal, or as directed by your healthcare practitioner.

Precautions

Caution: Discontinue use 2 weeks prior to surgery.

Warning: If pregnant or nursing, consult your healthcare practitioner before taking this product.

Keep out of reach of children.

Storage

Store in a cool, dry place.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

CoQ-10 ZEN by Natural Rhythm label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

CoQ-10 ZEN label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in CoQ-10 ZEN by Natural Rhythm

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Vegetable Capsule(s) Dosage formCapsule Servings per container30 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

L-Theanine

Interacts with
565 drugs
15 mg per serving

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong dro...

L-Theanine monograph & interactions

Coenzyme Q10

Interacts with
198 drugs
100 mg per serving

CoQ10 is a vitamin-like substance your body makes naturally that helps cells produce energy and acts as an antioxidant. It is generally well tolerated...

Coenzyme Q10 monograph & interactions

L-Carnitine

Interacts with
19 drugs
125 mg per serving Form: L-Carnitine Tartrate

L-carnitine is a compound your body makes naturally and also gets from foods like meat. It helps cells turn fat into energy, and supplements are most...

L-Carnitine monograph & interactions

Other (inactive) ingredients: Hypromellose, Microcrystalline Cellulose, Vegetarian Leucine. These complete the product’s ingredient list but are not active constituents.

Interaction report

CoQ-10 ZEN by Natural Rhythm Drug Interactions

Want to check YOUR meds against CoQ-10 ZEN?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
608Drugs
215 Moderate 393 Minor

Ingredients driving the most interactions

L-Theanine 565
Coenzyme Q10 198
L-Carnitine 19

Individual Drug Interactions

The ingredients in CoQ-10 ZEN interact with 608 drugs. Click any drug to see the details.

3 of the 3 ingredients in CoQ-10 ZEN interact with drugs. Each result below shows which ingredient is responsible. L-Theanine Coenzyme Q10 L-Carnitine

Each ingredient & the kinds of drugs it affects

For each ingredient in CoQ-10 ZEN with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

L-Theanine3 drug types · 565 drugs

Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Likelihood Unlikely Evidence D
Serotonergic Drugs

Clinical studies regarding the effects of L-theanine on serotonin levels are conflicting. Some studies suggest it can increase serotonin levels in the brain while others report that it may decrease them. Nevertheless, there have been no reports of l-theanine being a causative agent in serotonergic-related side effects or serotonin syndrome.

Likelihood Unlikely Evidence C
L-Theanine full monograph & interactions

Coenzyme Q103 drug types · 198 drugs

Alkylating Agents

Coenzyme Q10 has antioxidant effects. Theoretically, this may reduce the activity of chemotherapy drugs that generate free radicals.
Theoretically, antioxidants such as coenzyme Q10 might protect tumor cells from chemotherapeutic agents that work by inducing oxidative stress, such as alkylating agents (e.g., cyclophosphamide) and radiation therapy. The clinical importance of this interaction is unknown.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Coenzyme Q10 is chemically similar to menaquinone and might have vitamin K-like procoagulant effects, which could decrease the effects of warfarin.
Concomitant use of coenzyme Q10 and warfarin might reduce the anticoagulant effects of warfarin. Four cases of decreased warfarin efficacy thought to be due to coenzyme Q10 have been reported. However, there is some preliminary clinical research that suggests coenzyme Q10 might not significantly decrease the effects of warfarin in patients who have a stable INR.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, coenzyme Q10 might have additive effects with antihypertensive drugs.
Some clinical research shows that coenzyme Q10 can significantly lower blood pressure, although other studies have shown conflicting results.

Likelihood Possible Evidence B
Coenzyme Q10 full monograph & interactions

L-Carnitine3 drug types · 19 drugs

Acenocoumarol (Sintrom)

Theoretically, L-carnitine might increase the anticoagulant effects of acenocoumarol.
L-carnitine might enhance the anticoagulant effects of acenocoumarol, an oral anticoagulant similar to warfarin, but shorter-acting. There are at least two case reports of INR elevation with concomitant use. In one case, a 33-year-old male with a previously stable INR had an elevated INR of 4.65 after L-carnitine was started and continued for 10 weeks. INR normalized after discontinuation of the L-carnitine-containing product.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, L-carnitine might decrease the effectiveness of thyroid hormone replacement.
L-carnitine appears to act as a peripheral thyroid hormone antagonist by inhibiting entry of thyroid hormone into the nucleus of cells. Taking L-carnitine also seems to diminish some of the symptoms of hyperthyroidism.

Likelihood Probable Evidence B
Warfarin (Coumadin)

Theoretically, L-carnitine might increase the anticoagulant effects of warfarin.
L-carnitine might increase the anticoagulant effects of acenocoumarol, a shorter-acting oral anticoagulant similar to warfarin. There is not enough information to know whether this interaction occurs with L-carnitine and warfarin.

Likelihood Possible Evidence D
L-Carnitine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for CoQ-10 ZEN, from the product label.

Natural Rhythm

See all Natural Rhythm products
Name
Natural Rhythm
Street Address
1540 Keller Parkway Suite 108 #119
City
Keller
State
Texas
ZipCode
76248
Web Address
NaturalRhythm.co
Pharmacist Counseling Corner

CoQ-10 ZEN by Natural Rhythm: Common Questions

Does CoQ-10 ZEN by Natural Rhythm interact with any medications?
Yes. Based on its ingredients, CoQ-10 ZEN has a known interaction with 608 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
CoQ-10 ZEN contains 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What does L-theanine do in this product?
L-theanine is an amino acid that's possibly effective for supporting cognitive function. It may also have a mild calming effect, though the evidence for anxiety disorders isn't established.
Is CoQ10 the same as a vitamin?
No—CoQ10 is a natural compound your cells make to produce energy, not a vitamin. It's likely effective if you have a CoQ10 deficiency and possibly effective for heart health, migraines, and nerve pain.
What are the most common side effects?
L-carnitine and CoQ10 may cause gastrointestinal upset like nausea or diarrhea. L-theanine may cause headaches or drowsiness. At higher doses, L-carnitine can produce a fishy body odor.
Can I take this while pregnant or breastfeeding?
The facts show insufficient safety data for all three ingredients in pregnancy—it's best to avoid this product during pregnancy. For breastfeeding, CoQ10 is possibly safe but caution is advised; L-theanine and L-carnitine lack solid safety data. Talk with your doctor or pharmacist first.
Will this interact with my blood pressure medication?
Possibly. Both L-theanine and CoQ10 may lower blood pressure, so combined with your medication they could lower it further. Check your specific blood pressure drug with the tool on this page and confirm with your pharmacist.
Can this interfere with warfarin or other blood thinners?
Yes—this is a significant concern. L-carnitine may increase warfarin's effect, raising bleeding risk, while CoQ10 may reduce it. If you take any blood thinner, use the medication checker and talk with your pharmacist before starting.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

CoQ-10 ZEN label
Go deeper

The Full Monographs Behind CoQ-10 ZEN’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Theanine

Interacts with 565 drugs

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong drowsiness. Early research suggests it may...

Read the full Theanine monograph → Herb & supplement monograph

Coenzyme Q10

Interacts with 198 drugs

CoQ10 is a vitamin-like substance your body makes naturally that helps cells produce energy and acts as an antioxidant. It is generally well tolerated and is most studied for heart condition...

Read the full Coenzyme Q10 monograph → Herb & supplement monograph

L-carnitine

Interacts with 19 drugs

L-carnitine is a compound your body makes naturally and also gets from foods like meat. It helps cells turn fat into energy, and supplements are most clearly useful for people with a true ca...

Read the full L-carnitine monograph →
Sources

Sources & How We Checked

CoQ-10 ZEN's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 87 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Theanine 6 references
  1. Yokogoshi H, Kobayashi M. Hypotensive effect of gamma-glutamylethylamide in spontaneously hypertensive rats. Life Sci 1998;62:1065-8.
  2. Haskell, C. F., Kennedy, D. O., Milne, A. L., Wesnes, K. A., and Scholey, A. B. The effects of L-theanine, caffeine and their combination on cognition and mood. Biol.Psychol. 2008;77(2):113-122. PubMed
  3. Yokogoshi, H., Kato, Y., Sagesaka, Y. M., Takihara-Matsuura, T., Kakuda, T., and Takeuchi, N. Reduction effect of theanine on blood pressure and brain 5-hydroxyindoles in spontaneously hypertensive rats. Biosci.Biotechnol.Biochem. 1995;59(4):615-618. PubMed
  4. Lyon MR, Kapoor MP, Juneja LR. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial. Altern Med Rev. 2011;16(4):348-
  5. Hidese S, Ota M, Wakabayashi C, et al. Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study. Acta Neuropsychiatr 2017;29(2):72-9.
  6. Tsuchiya T, Honda H, Oikawa M, et al. Oral administration of the amino acids cystine and theanine attenuates the adverse events of S-1 adjuvant chemotherapy in gastrointestinal cancer patients. Int J Clin Oncol 2016;21(6):1085-90. PubMed

See these in context on the Theanine monograph →

Coenzyme Q10 40 references
  1. Kamikawa T, Kobayashi A, Yamashita T, et al. Effects of coenzyme Q10 on exercise tolerance in chronic stable angina pectoris. Am J Cardiol 1985;56:247-51. PubMed
  2. Langsjoen P, Willis R, Folkers K. Treatment of essential hypertension with coenzyme Q10. Mol Aspects Med 1994;S265-72. PubMed
  3. Spigset O. Reduced effect of warfarin caused by ubidecarenone. Lancet 1994;334:1372-3. PubMed
  4. 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;13:203-8. PubMed
  5. Portakal O, Ozkaya O, Erden Inal M, et al. Coenzyme Q10 concentrations and antioxidant status in tissues of breast cancer patients. Clin Biochem 2000;33:279-84. PubMed
  6. Lund EL, Quistorff B, Spang-Thomsen M, Kristjansen PE. Effect of radiation therapy on small-cell lung cancer is reduced by ubiquinone intake. Folia Microbiol (Praha) 1998;43:505-6. PubMed
  7. Langsjoen PH, Langsjoen PH, Folkers K. Long-term efficacy and safety of coenzyme Q10 therapy for idiopathic dilated cardiomyopathy. Am J Cardiol 1990;65:521-3. PubMed
  8. Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm 2000;57:1221-7. DOI
  9. Landbo C, Almdal TP. [Interaction between warfarin and coenzyme Q10]. Ugeskr Laeger 1998;160:3226-7.
  10. Baggio E, Gandini R, Plauncher AC, et al. Italian multicenter study on the safety and efficacy of coenzyme Q10 as adjunctive therapy in heart failure. CoQ10 Drug Surveillance Investigators. Mol Aspects Med 1994;15 Suppl:S287-94. PubMed
  11. Burke BE, Neuenschwander R, Olson RD. Randomized, double-blind, placebo-controlled trial of coenzyme Q10 in isolated systolic hypertension. South Med J 2001;94:1112-7. PubMed
  12. The Huntington Study Group. A randomized, placebo-controlled trial of coenzyme Q10 and remacemide in Huntington's disease. Neurology 2001;57:397-404.
  13. Hodgson JM, Watts GF, Playford DA, et al. Coenzyme Q10 improves blood pressure and glycaemic control: a controlled trial in subjects with type 2 diabetes. Eur J Clin Nutr 2002;56:1137-42. PubMed
  14. Singh RB, Neki NS, Kartikey K, et al. Effect of coenzyme Q10 on risk of atherosclerosis in patients with recent myocardial infarction. Mol Cell Biochem 2003;246:75-82. DOI
  15. Porterfield LM. Why did the response to warfarin change? RN 2000;63:107.
  16. Sandor PS, Di Clemente L, Coppola G, et al. Efficacy of coenzyme Q10 in migraine prophylaxis: A randomized controlled trial. Neurology 2005;64:713-5. PubMed
  17. Engelsen J, Nielsen JD, Winther K. Effect of coenzyme Q10 and Ginkgo biloba on warfarin dosage in stable, long-term warfarin treated outpatients. A randomised, double blind, placebo-crossover trial. Thromb Haemost 2002;87:1075-6. DOI
  18. 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 Cardiol 2004;27:295–9. PubMed
  19. Storch A, Jost WH, Vieregge P, et al. Randomized, double-blind, placebo-controlled trial on symptomatic effects of coenzyme Q10 in Parkinson disease. Arch Neurol 2007;64:938-44. DOI
  20. Digiesi V, Cantini F, Oradei A, et al. Coenzyme Q10 in essential hypertension. Mol Aspects Med 1994;15 Suppl:s257-63. PubMed
  21. Yamagami T, Takagi M, Akagami H, et al. Effect of coenzyme Q10 on essential hypertension, a double blind controlled study. In: Folkers KA, Yamamura Y, eds. Biomedical and Clinical Aspects of Coenzyme Q, Vol. 5. Amsterdam: Elsevier Science Publications, 19
  22. Ho MJ, Bellusci A, Wright JM. Blood pressure lowering efficacy of coenzyme Q10 for primary hypertension (review). Cochrane Database Syst Rev 2009;(4):CD007435. PubMed
  23. Rosenfeldt, F. L., Haas, S. J., Krum, H., Hadj, A., Ng, K., Leong, J. Y., and Watts, G. F. Coenzyme Q10 in the treatment of hypertension: a meta-analysis of the clinical trials. J Hum.Hypertens. 2007;21(4):297-306. PubMed
  24. Stamelou, M., Reuss, A., Pilatus, U., Magerkurth, J., Niklowitz, P., Eggert, K. M., Krisp, A., Menke, T., Schade-Brittinger, C., Oertel, W. H., and Hoglinger, G. U. Short-term effects of coenzyme Q10 in progressive supranuclear palsy: a randomized, place DOI
  25. Keogh A, Fenton S, Leslie C, et al. Randomised double-blind, placebo-controlled trial of coenzyme Q, therapy in class II and III systolic heart failure. Heart Lung Circ. 2003;12:135-41.
  26. Gane, E. J., Weilert, F., Orr, D. W., Keogh, G. F., Gibson, M., Lockhart, M. M., Frampton, C. M., Taylor, K. M., Smith, R. A., and Murphy, M. P. The mitochondria-targeted anti-oxidant mitoquinone decreases liver damage in a phase II study of hepatitis C
  27. Lynch, D. R., Perlman, S. L., and Meier, T. A phase 3, double-blind, placebo-controlled trial of idebenone in friedreich ataxia. Arch Neurol. 2010;67(8):941-947. PubMed
  28. Young, J. M., Florkowski, C. M., Molyneux, S. L., McEwan, R. G., Frampton, C. M., Nicholls, M. G., Scott, R. S., and George, P. M. A randomized, double-blind, placebo-controlled crossover study of coenzyme Q10 therapy in hypertensive patients with the me
  29. Ishiyama, T., Morita, Y., Toyama, S., Yamagami, T., and Tsukamoto, N. A clinical study of the effect of coenzyme Q on congestive heart failure. Jpn.Heart J 1976;17(1):32-42. PubMed
  30. Matthews, P. M., Ford, B., Dandurand, R. J., Eidelman, D. H., O'Connor, D., Sherwin, A., Karpati, G., Andermann, F., and Arnold, D. L. Coenzyme Q10 with multiple vitamins is generally ineffective in treatment of mitochondrial disease. Neurology 1993;43(5
  31. Malm, C., Svensson, M., Sjoberg, B., Ekblom, B., and Sjodin, B. Supplementation with ubiquinone-10 causes cellular damage during intense exercise. Acta Physiol Scand. 1996;157(4):511-512. PubMed
  32. Singh, R. B., Wander, G. S., Rastogi, A., Shukla, P. K., Mittal, A., Sharma, J. P., Mehrotra, S. K., Kapoor, R., and Chopra, R. K. Randomized, double-blind placebo-controlled trial of coenzyme Q10 in patients with acute myocardial infarction. Cardiovasc. PubMed
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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