Report on Coenzyme Q10 Side Effects and Usage

Coenzyme Q10

Natural health supplements sometimes have unexpected side effects or interactions with medication that can lead to adverse reactions that are sometimes life threatening. The following is a list of cautions that you should be aware of before using coenzyme Q10 (ubiquinone). This oil-soluble, vitamin-like substance is what the body uses to generate energy.

Warning 1 – Anticoagulants: Coenzyme Q10 decreases the effectiveness of anticoagulants such as Warfarin (Coumadin). Use caution when combining with ginkgo, ibuprofen, aspirin, and other NSAIDs.

Warning 2 – Oral antidiabetics: Oral antidiabetics may decrease the action of CoQ10 and deplete the body’s stores of this vitamin-like substance.

Warning 3 – Beta-blockers: Beta-blockers may decrease the action of CoQ10 and deplete endogenous stores.

Warning 4 – HMG-coa reductase inhibitors: HMG-coa reductase inhibitors may decrease the action of CoQ10 and deplete the body’s stores of this antioxidant.

Warning 5 – Phenothiazines: Some phenothiazines may decrease the action of CoQ10 and deplete endogenous stores.

Warning 6 – Tricyclic antidepressants: Tricyclic antidepressants may decrease the action of CoQ10 and deplete endogenous stores.

Warning 7 – Surgery: The use of CoQ10 supplements is controversial as some sources assert that it improves heart function if taken before surgery and other sources say to discontinue if you are scheduled for surgery in the next two weeks. Talk to your doctor about the use of CoQ10 before surgery.

Warning 8 – Antihypertensive drugs: Coenzyme Q-10 seems to decrease blood pressure. Taking CoQ-10 with medications for high blood pressure may cause blood pressure to go too low. Medications in this class include Amlodipine (Norvasc), diltiazem (Cardizem), captopril (Capoten), enalapril (Vasotec), furosemide (Lasix), hydrochlorothiazide (HydroDIURIL), losartan (Cozaar), valsartan (Diovan), and many others.

Warning 9 – Statins: The use of statins (cholesterol-lowering drugs) reduces serum levels of coenzyme Q10 by up to 40%. Some research suggests that supplementation with coenzyme Q10 would be beneficial as a routine adjunct to treatment with statins.

Co-enzyme Q10 is produced by the human body and is necessary for the basic functioning of cells. Used as a supplement Coenzyme Q-10 is used internally for its beneficial effects on:

  • Anti-aging (extended lifespan 50% when given to very old mice (Bliznakov, 1973))
  • Cancer
  • Coenzyme Q10 may be useful in treating hypertension by lowering systolic blood pressure by up to 17 mm Hg and diastolic blood pressure by up to 10 mm Hg without significant side-effects.
  • Congestive heart failure, heart disease
  • Diabetes
  • Huntington’s disease
  • Improving athletic performance
  • Migraine headaches dosages of 150 to 300 mg/day.
  • Mitochondrial cytopathies
  • Parkinson’s disease
  • Periodontal disease
  • Radiation injury
  • Reducing the risk of heart disease among menopausal women
  • Relief from the side effects of cancer treatment
  • Stroke
  • Tumors
  • Viral diseases including HIV/AIDS

Side Effects of Co-enzyme Q10

While CoQ10 is safe for most adults it can cause some mild side effects including:

  1. gastrointestinal (GI) upset if taken on an empty stomach
  2. loss of appetite
  3. nausea
  4. vomiting
  5. diarrhea

Taking small amounts 2 or 3 times a day instead of a large dose all at once can help reduce side effects. In rare cases it can cause allergic skin rashes. Other side effects may also occur when using coenzyme Q10. (See form below)

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