Turmeric and warfarin, what to check before you start

If you take warfarin, you'll already know how much attention goes into keeping your blood test steady, so it makes sense to ask before adding anything new to your day, turmeric included.

Turmeric and warfarin can interact, so check before combining them. The Welsh Medicines Advice Service describes one person whose previously stable INR, the blood test that tracks warfarin, rose to a level linked with a serious risk of bleeding after they started a product containing turmeric. Once stable, the NHS usually checks INR every 12 weeks.

Key takeaways

• Turmeric may affect clotting when taken in large amounts, and curcumin might slow the rate your body clears warfarin.
• Most of the evidence comes from lab and animal studies, plus a small number of human case reports.
• The concern is mainly with medicinal doses and concentrated curcumin supplements rather than turmeric used in cooking.
• The NHS advice is to tell your doctor about any herbal remedy or supplement before you start it.
• Know the signs of bleeding, and call NHS 111 if you notice them.

Can you take turmeric and warfarin together?

Only after speaking to your anticoagulation clinic, GP, or pharmacist, who may want to check your INR more closely when you start.

That isn't the same as "never". It's what the NHS advice on warfarin says about every herbal remedy and supplement: tell your doctor if you take any, and speak to your doctor before starting anything new. Turmeric is one of the herbs where there's a specific reason to follow that advice.

Why might turmeric affect warfarin?

There are two possible routes, and both are still being worked out.

Warfarin is defined as an anticoagulant, a medicine that makes your blood take longer to clot. People taking it have regular INR tests, which measure how long their blood takes to clot, and their dose may change based on the results. Too low and it isn't protecting you, too high and the risk of bleeding goes up.

The Welsh Medicines Advice Service sets out how turmeric could tip that balance. Turmeric may interfere with clotting by reducing platelet aggregation, the clumping of tiny blood cells that starts a clot. And curcumin might decrease the clearance of warfarin, meaning more of the medicine stays in your body for longer. Either would push in the same direction as warfarin itself, which is why it advises monitoring closely.

What does the evidence show?

Dose comes first, and it's the part most often missed.

Nearly all of the reported or theoretical interactions relate to medicinal doses of turmeric or concentrated curcumin extract supplements, not to the turmeric in a curry. The Welsh Medicines Advice Service advises clinicians to weigh the nature and dose of the product when they assess any risk.

The caveat is that the evidence base is small and mostly indirect. Much of it is in vitro or animal work that may not be clinically relevant in people:

• A laboratory study found turmeric extracts could reduce platelet aggregation in a test tube.
• A study in rats found curcumin raised blood levels of both warfarin and clopidogrel. In that study, the change in levels didn't alter clotting time or platelet aggregation, which shows how hard these results are to translate.
• A report from France's pharmacovigilance network described a raised INR in a person taking turmeric alongside fluindione, an anticoagulant that works in the same way as warfarin.

Direct evidence on turmeric drinks is limited, so nobody can promise that a shot makes no difference to your INR. That's exactly why the person monitoring it should know.

Does cooking with turmeric count?

Turmeric as a spice in food isn't where the concern lies, but a new daily habit is worth mentioning.

The NHS advice for people on warfarin is to talk to a doctor before making big changes to your diet, because what you eat can affect how warfarin works. Your usual curry isn't a big change. Starting a supplement, a daily turmeric drink, or a run of golden lattes every morning is the kind of new routine your clinic would want to hear about, partly so they can check your INR if needed.

What else should you avoid on warfarin?

The NHS names a few things to steer clear of, and the turmeric question sits alongside them.

On warfarin, the NHS advises against St John's wort and vitamin K supplements, and against large amounts of alcohol, cranberry juice, and grapefruit juice. The Welsh Medicines Advice Service also lists other herbs that may add to bleeding risk, including garlic, ginkgo, Panax ginseng, and ginger. A systematic review of 78 foods and herbs in the British Journal of Clinical Pharmacology named ginger among those that may raise bleeding risk with warfarin.

That ginger point matters if you're choosing a shot, because many turmeric drinks, including several of ours, combine the two. Raw Turmeric Original is the one in our range without ginger, which is worth knowing when you speak to your clinic.

What are the signs of bleeding to watch for?

The NHS lists the symptoms of serious bleeding on warfarin, and they're worth knowing whether or not you take turmeric:

• Blood in your pee or poo
• Unexplained bruising or nosebleeds
• Coughing up blood, or vomiting blood
• A sudden, bad headache, especially with confusion or slurred speech

Call NHS 111 if you're taking warfarin and notice signs of bleeding, or if you've had a head injury. The NHS also suggests carrying your anticoagulant alert card, so anyone treating you knows you take warfarin.

Where does a turmeric shot fit if you take warfarin?

Only once your clinic agrees, and with your INR checked as they advise.

Our shots are juiced whole-food drinks, so they carry far less curcuminoid than a concentrated curcumin capsule, which is where most of the interaction concern lies. Even so, there's no direct research on turmeric drinks and warfarin, so that difference is a reason to have the conversation with your clinic, not a reason to skip it.

If your clinic is happy, Raw Turmeric Original is the simplest place to start. It's raw turmeric root at 30% in a cold-crushed, whole watermelon-based blend with pineapple, lemon, magnesium, and vitamin C, plus our trade-secret BioMax Uptake Blend®, which includes black pepper, at a 0.1% inclusion. It contains no ginger, so there's one fewer ingredient for your clinic to weigh up.

The takeaway

Turmeric and warfarin can interact, mainly at medicinal doses and with concentrated curcumin supplements, and the evidence is mostly lab and animal work plus a few human case reports. That's enough for the NHS advice to apply: tell your anticoagulation clinic, GP, or pharmacist before you start, let them decide whether your INR needs checking, and know the signs of bleeding.

Once your clinic agrees, a single Raw Turmeric Original each morning is a steady, consistent way to make turmeric part of your routine, which is exactly the kind of habit warfarin care likes best.

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