CoQ10 Dosage and Timing: How Much, When and With What

How much CoQ10 to take, when to take it and whether it can go down with fish oil are the questions readers ask us most. We used to answer them in ten separate posts. This page puts the answers in one place, with what the research supports and where it is silent.

This is general information, not medical advice. If you take prescription medicine, particularly a blood thinner, check with a pharmacist first.

How much

There is no official recommended daily amount for CoQ10, because the body makes its own. Studies in adults have most often used 100 to 300 mg a day, and amounts up to 1,200 mg have been used in research without serious side effects, according to the NIH's National Center for Complementary and Integrative Health.

A practical approach:

• Starting out: 100 mg a day is common and inexpensive.
• Popular middle ground: 200 mg a day.
• Higher amounts (300 mg and up) are usually suggested by a clinician for a specific reason, and are typically split across the day.

More is not automatically better. CoQ10 is absorbed slowly and incompletely, and absorption per dose seems to flatten at higher amounts, which is the main reason larger daily totals are divided.

Taking 200 mg

If your bottle is 200 mg per capsule, one capsule with a meal is the usual instruction. If you take 400 mg or more a day, two separate doses with two different meals is a reasonable way to spread it out. Follow the label unless your clinician says otherwise.

Take it with food that has some fat

CoQ10 is fat-soluble. Taking it with a meal that contains fat, such as eggs, yogurt, nuts, olive oil or fish, helps absorption. Taking it on an empty stomach with water is the least effective option.

Morning or night?

No study has shown that one time of day works better than another. What matters more is taking it consistently, with food.

There is one practical point: a minority of people report trouble sleeping on CoQ10. If that happens, move it to breakfast or lunch. If it doesn't bother you, take it with whichever meal you are least likely to skip.

With fish oil

Taking CoQ10 and fish oil together is fine for most people, and convenient, since both are fat-soluble and absorb better with a meal. Both can have mild effects on blood clotting and blood pressure, so if you take warfarin or another blood thinner, ask your doctor before combining them.

Long-term use

People commonly take CoQ10 for months or years. Trials lasting a year or longer have not flagged serious safety problems, and the most common complaints are mild stomach upset, nausea and sleep trouble. If you take it long term, it is sensible to:

• tell your doctor and pharmacist, so it is on your medication list
• review it if you start a new prescription, especially warfarin, blood pressure medicine or cancer treatment
• recheck the label when you rebuy, since formulations change

Timing for fertility

Fertility trials have typically given CoQ10 daily for about two to three months, because eggs and sperm take roughly that long to mature. There is no evidence that the time of day matters. More detail is in CoQ10 and Fertility.

Related guides

• CoQ10 Supplements: How to Choose One
• Ubiquinol vs. Ubiquinone