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Coenzyme Q10

By

Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Last full review/revision Jan 2022| Content last modified Jan 2022
CLICK HERE FOR THE PROFESSIONAL VERSION

What is coenzyme Q10?

Coenzyme Q10 (ubiquinone) is an enzyme that is naturally produced in the body. Cells use it to produce and manage energy. It also has an antioxidant effect. Antioxidants Antioxidants The human body needs various vitamins and minerals in order to thrive. Many of these nutrients can be found in whole, non-processed foods such as fruits and vegetables. However, most modern... read more protect cells against damage by free radicals, which are highly chemically active by-products of normal cell activity.

The levels of coenzyme Q10 seem to be lower in older people and in people with chronic diseases, such as heart problems, cancer, Parkinson disease, diabetes, HIV infection or AIDS, and muscular dystrophies. However, it is not known whether these low levels contribute to these disorders.

  • In addition to being naturally made in the body, coenzyme Q10 is in foods such as meat, fish, and vegetable oils.

  • A synthetic form of coenzyme Q10 is available as a dietary supplement.

What claims are made about coenzyme Q10?

Coenzyme Q10 is said to be useful because of its antioxidant effect and role in energy metabolism. Antioxidants protect cells against damage by free radicals, which are highly chemically active by-products of normal cell activity.

Proponents claim coenzyme Q10 (CoQ10) improves skin appearance, exercise performance, fertility, brain and lung health, and migraines. Specifically, it is said to benefit people with

Coenzyme Q10 may also help protect the heart from the toxic effects of certain cancer chemotherapy drugs (such as doxorubicin and daunorubicin). Proponents also claim that coenzyme Q10 can decrease the muscle symptoms that can result from taking statins.

Does coenzyme Q10 work?

Because people with some diseases have reduced levels of coenzyme Q10, scientists have studied whether coenzyme Q10 supplements have health benefits. These studies are not conclusive. Some preliminary studies suggest coenzyme Q10 may possess protective properties, but more testing is needed.

What are the possible side effects of coenzyme Q10?

Side effects are uncommon, but some people have

  • Digestive symptoms, such as abdominal pain, nausea, heartburn, diarrhea, and vomiting

  • Central nervous system symptoms, such as dizziness, light sensitivity, irritability, and headache

  • Skin itching

  • Rash

  • Loss of appetite

  • Fatigue

  • Flu-like symptoms

What drug interactions occur with coenzyme Q10?

Coenzyme Q10 supplements may interact with some antihypertensive (those that lower blood pressure) and chemotherapy drugs.

Coenzyme Q10 may increase the risk of blood clots in people who take the anticoagulant warfarin by decreasing warfarin's effectiveness.

Recommendations

Coenzyme Q10 may help protect the heart from the toxic effects of certain cancer chemotherapy drugs (such as doxorubicin and daunorubicin) and may benefit people with heart disease.

Coenzyme Q10 appears reasonably safe.

People taking warfarin should consult their doctor before taking coenzyme Q10.

NOTE: This is the Consumer Version. DOCTORS: CLICK HERE FOR THE PROFESSIONAL VERSION
CLICK HERE FOR THE PROFESSIONAL VERSION
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