Short answer

We found no direct interaction between CoQ10 and Vitamin C in the sources below, but they share a caution.

Both have a note about cancer treatment; check with your care team.

CoQ10

What it is: A compound the body makes, found at high levels in the heart, liver and kidneys.

What the research says: Studies on heart disease are inconclusive. Overall, it doesn't seem to relieve muscle pain from statins, and it probably doesn't lower blood pressure meaningfully.

Cautions

• No serious side effects reported; it can cause mild insomnia or stomach upset.

Medicines to check

• Warfarin (blood thinner) and insulin
• Some cancer treatments: check with your care team

In Holitro: CoQ10 (200 mg per capsule)

Source: NIH National Center for Complementary and Integrative Health: Coenzyme Q10 (updated January 2019)

Vitamin C

What it is: An antioxidant vitamin the body needs to make collagen, absorb iron from plant foods and support the immune system.

What the research says: Vitamin C is essential; supplements make sure you get enough if your diet falls short.

Cautions

• Adults shouldn't exceed 2,000 mg a day; too much can cause diarrhea, nausea and cramps.
• People with hemochromatosis should avoid high doses.

Medicines to check

• Chemotherapy and radiation: check with your care team first
• In one study, antioxidants including vitamin C reduced the benefit of a statin plus niacin

In Holitro: Vitamin C (1000 mg per capsule)

Source: NIH Office of Dietary Supplements: Vitamin C: Fact Sheet for Consumers (updated March 2021)

Check with your doctor or pharmacist, especially if you take medication.

Check your stack — free

Educational information only, not medical advice. This reflects general ingredient overlap, not a personalized safety review. Always check with your doctor or pharmacist before combining supplements, especially if you take medication, are pregnant or nursing, or manage a health condition. These statements have not been evaluated by the FDA.