Blog · Medicines
CoQ10 and Warfarin: A Pair That Needs INR Checks
CoQ10 and warfarin can interact. NCCIH names a warfarin interaction, and Memorial Sloan Kettering says CoQ10 may work against the drug. The Linus Pauling Institute advises INR checks if you combine them. Synaptril contains CoQ10 in an unlisted amount, so ask your prescriber before starting.
Written by the Synaptril label deskUpdated · 4 min read
The interaction01
Does CoQ10 interact with warfarin?
Yes, CoQ10 can interact with warfarin. It may lessen the drug's effect, which means a higher chance of clotting if the dose is not adjusted.
NCCIH lists a warfarin interaction for CoQ10 (NCCIH, Coenzyme Q10). Memorial Sloan Kettering says CoQ10 may antagonize warfarin (MSKCC, Coenzyme Q10). Both treat it as a reason for caution, not an absolute ban. The Linus Pauling Institute still rates CoQ10 as safe at doses up to 1,200 mg for most adults, so the worry is the drug pairing, not the compound itself.
The effect varies from person to person, which is why monitoring is the standard answer.
Warfarin keeps blood from clotting too easily. If anything weakens it, a clot becomes more likely, and clots can lead to stroke. That is why this is worth a phone call and not a guess.
Monitoring02
What is an INR check and why does it matter?
An INR check is a blood test that shows how quickly your blood clots. Warfarin doses are set from it.
The Linus Pauling Institute advises INR monitoring if you take CoQ10 with warfarin (Linus Pauling Institute, Coenzyme Q10). If a supplement shifts the effect, the test is how your clinic notices.
Tell the clinic before you start, and again if you stop. Most clinics are glad to be asked, and a pharmacist can often answer by phone. Ask them to write the answer on your record so any later prescriber sees it too. A change in either direction can alter your readings.
It also helps to keep the dose steady. A supplement taken on some days and skipped on others makes the readings harder to read.
| Detail | Why it helps |
|---|---|
| Product name and start date | Lets them read later INR changes correctly |
| One capsule a day | Shows the dose is constant |
| Ingredients with CoQ10 and turmeric | Both are flagged for blood thinners |
| The date you stop | Signals that the effect may reverse |
On the bottle03
How much CoQ10 does Synaptril have?
Synaptril likely has under about 35 mg of CoQ10 per capsule, as ubiquinone. That is our estimate, because the label gives only the 575 mg blend total (21 CFR 101.36, supplement labeling).
A low amount can still matter on a narrow-margin drug, and the same capsule holds turmeric, another flagged ingredient. Our supplements and medicines guide covers both.
Turmeric pulls the other way. It may raise bleeding risk, while CoQ10 may weaken the drug. Two opposite pushes in one capsule, each of unknown size, make the net effect hard to predict, which is another reason to ask.
Synaptril: from $49 a bottle30 capsules · 2, 3 or 6 bottles · free shipping on 3 or 6 · 60-day money-back guarantee
See packsA safe order04
What is a careful way to proceed?
A careful way is to ask first, start only with agreement and review early. The steps below follow the label's own routine, with one change: the first step is a conversation, not a purchase.
That order protects you. A short call before the first capsule costs nothing, and it turns a guess into a plan that your clinic can monitor from day one.
- 01
Check the seal
The label says not to use the bottle if the safety seal is damaged or missing. Look before the first capsule, and keep the bottle below 30°C (86°F).
- 02
Take one capsule
One capsule is one serving, and the label stops at one a day. Swallow it with water. Never double up after a missed day.
- 03
Pick one time a day
The label sets no time of day. Many people tie it to breakfast or another daily habit. Keep any prescribed medicine on its usual schedule.
- 04
Review before day 60
The money-back guarantee runs 60 days from purchase. Note how you feel at day 30, and decide well before the window closes.
Keep taking warfarin exactly as prescribed. Never change the dose yourself.
Your choice05
Is Synaptril a poor fit if you take warfarin?
It may be. Two flagged ingredients, no published amounts and no study of the capsules make it a hard product to judge for a person on a blood thinner. Many readers will decide to skip it, and that is a reasonable choice.
If your prescriber approves it, you still have the label's own advice to consult a physician, and a 60-day window to stop. Keep a note of the date you began so the clinic can line it up with each INR result.
The same goes for the day you stop. Many people forget that ending a supplement is also a change, and the INR can move again afterward.
American Synaptril authorized shop
Ready to try Synaptril?
Start with a medicine check, then choose your pack. Three or six bottles cost less per bottle and ship free, and each pack comes with the 60-day money-back guarantee.
- Secure checkout
- 60-day money-back guarantee
- Ships from the U.S.
FAQ06
CoQ10 and blood thinner questions
How soon after starting CoQ10 would INR change?
Our sources give no fixed time. That is why clinics ask for a check soon after any new supplement starts, often within the first couple of weeks.
Should I stop CoQ10 before a warfarin dose change?
Do not change anything on your own. Tell the clinic about the supplement, and let them decide how to time any change so the INR stays readable.
Does ubiquinol act differently on warfarin?
Our sources describe the interaction for CoQ10 in general and do not separate the two forms. Treat both forms as a flagged ingredient.
Do newer blood thinners have the same problem?
Our sources focus on warfarin. Other blood thinners work differently, so ask the pharmacist about your own drug rather than assuming it is safe.
Who wrote this07
Written and reviewed by
Pages built from the label, the sales page and linked NIH, FDA, CDC, FTC and peer-reviewed sources.
Last updated . Read our editorial standards and how we check reviews. This website is run by an American Synaptril authorized shop, not by the manufacturer or the distributor. We earn money when you buy through our order links.
Keep reading
More about Synaptril
American Synaptril authorized shop
Ready to try Synaptril?
Start with a medicine check, then choose your pack. Three or six bottles cost less per bottle and ship free, and each pack comes with the 60-day money-back guarantee.
- Secure checkout
- 60-day money-back guarantee
- Ships from the U.S.