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What Are the Side Effects of CoQ10?
CoQ10 side effects are usually mild: NCCIH reports no serious ones, though insomnia or digestive upset may occur. The one interaction to know is warfarin, which CoQ10 may weaken. Synaptril lists CoQ10 last in its blend, so anyone on warfarin should ask a prescriber first.
Written by the Synaptril label deskUpdated · 4 min read
What are the side effects of CoQ10?
The side effects of CoQ10 are mild in the sources we hold: trouble sleeping and stomach upset.
| Effect | Source |
|---|---|
| Insomnia | NCCIH (NCCIH, Coenzyme Q10) |
| Digestive upset | NCCIH (NCCIH, Coenzyme Q10) |
| Weaker warfarin effect | Linus Pauling Institute (Linus Pauling Institute, Coenzyme Q10) |
NCCIH reports no serious side effects. Mild ones are the norm, but the warfarin report is the one that can matter for health.
Does CoQ10 interact with warfarin?
Yes, it has been reported to reduce warfarin's effect. People on warfarin should consult their prescriber and have INR checked (Linus Pauling Institute, Coenzyme Q10).
Side effects can also come from the other lines in the blend, such as stomach upset from turmeric or L-carnitine. The full list is on the side effects page.
We hold no source on blood pressure medicines, so we will not say whether CoQ10 affects them. The label asks you to consult a physician if you take any medication.
Is a CoQ10 capsule right for you?
Answer five yes/no questions for a quick read.
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See packsHow much CoQ10 is in Synaptril?
At most about 35 mg a capsule, by the blend math. Retail products usually give 30 to 100 mg (Linus Pauling Institute, Coenzyme Q10). Trials ran from about 30 to 300 mg for the heart and 300 to 2,400 mg for neurological conditions, so the capsule is far below the high doses.
Keep taking prescribed medicine. See Synaptril side effects, supplements and medicines and the CoQ10 profile.
FAQ01
Synaptril questions people ask
Can CoQ10 cause insomnia?
It can. NCCIH lists insomnia among the possible effects, along with digestive upset. Tell your pharmacist if sleep changes after you start.
Is CoQ10 safe to take every day?
NCCIH reports no serious side effects. Ask a pharmacist if you take other medicines.
How long does CoQ10 stay in the body?
We hold no source on that, so we will not guess. Ask your pharmacist.
How would I know if CoQ10 affects my warfarin?
Your prescriber checks it with an INR blood test. The Linus Pauling Institute advises people on warfarin to consult their prescriber and have INR checked. Never adjust the dose yourself.
Who wrote this02
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Pages built from the label, the sales page and linked NIH, FDA, CDC, FTC and peer-reviewed sources.
Last updated . Learn about our editorial standards and how we check reviews. This website is run by a U.S. retail partner of Synaptril, not by the manufacturer or the distributor. We make money when you buy through our order links.
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