Ginkgo Biloba and Blood Thinner Interactions: What You Need to Know
Nov, 19 2025
More than 12 million Americans take Ginkgo biloba supplements every year, mostly for memory or circulation. But if you're on a blood thinner-whether it's warfarin, aspirin, clopidogrel, or one of the newer DOACs like apixaban-you need to pause and think before taking it. The problem isn't just about one herb. It's about what happens when something natural meets powerful medicine.
What Is Ginkgo Biloba, Really?
Ginkgo biloba comes from the leaves of a tree that’s been around for over 270 million years. It’s one of the oldest living tree species on Earth. The extract used in supplements is standardized as EGb 761, which means it has a consistent mix of active compounds: 24% flavonol glycosides and 6% terpene lactones. This specific blend makes up about 70% of all Ginkgo products sold globally.
It’s not just a trendy supplement. It’s been used in Chinese medicine for centuries and entered Western medicine in the 1950s. Today, the global market for Ginkgo is worth nearly $2 billion, and it’s growing. But here’s the catch: most of the research on its safety comes from studies using this exact standardized extract. Many store-bought supplements aren’t made the same way.
How Ginkgo Might Affect Blood Thinning
Ginkgo doesn’t work like warfarin or aspirin. It doesn’t directly thin your blood. Instead, it affects platelets-the tiny cells in your blood that clump together to form clots. Research shows Ginkgo can block signals that make platelets sticky. That’s why some scientists think it might increase bleeding risk.
It also interacts with liver enzymes, especially CYP2C9, which is how your body breaks down warfarin. If Ginkgo slows that process down, warfarin sticks around longer. That could make your blood too thin. That’s the theory.
But here’s where it gets messy. In controlled clinical trials, researchers gave people Ginkgo along with aspirin or warfarin and found no major increase in bleeding. One study even showed no change in clotting times. So why do doctors still warn about it?
The Case Reports That Changed Everything
While lab studies say Ginkgo is safe, real-life stories don’t. Between 2008 and 2020, the FDA received 18 reports of bleeding events linked to Ginkgo use. These weren’t just nosebleeds. They included brain bleeds, internal bleeding after surgery, and unexplained bruising. In nearly every case, the person was also taking a blood thinner.
The problem? Most of these cases involved non-standardized Ginkgo products. Some had unknown doses. Others were contaminated. One study found that 21% of patients taking blood thinners were also using herbal supplements like Ginkgo-and almost half of them were at risk for dangerous interactions.
That’s why the Mayo Clinic and GoodRx say: avoid Ginkgo if you’re on warfarin. They call it a "high-risk" interaction. The Cleveland Clinic lists blood thinners as a direct contraindication. But the American Society of Health-System Pharmacists says the risk is "theoretical." What gives?
Why Experts Disagree
The divide comes down to evidence type. Controlled studies? Mostly safe. Case reports? Often dangerous. The difference? Quality.
Studies using EGb 761-the gold-standard extract-show little to no interaction. But the supplements you buy at the grocery store? They might not even contain that extract. Some have less than half the active ingredients. Others have contaminants that affect clotting. A 2023 survey found that 42% of Ginkgo labels now warn about blood thinners-up from 28% in 2018. That’s because manufacturers are seeing the same case reports you are.
Dr. Michael Murray recommends stopping Ginkgo 36 hours before surgery. Dr. Tieraona Low Dog says two weeks. The American Society of Anesthesiologists agrees with the two-week rule. But the American College of Chest Physicians says there’s no proof you need to stop it at all. So which do you follow?
What the Data Says About Specific Blood Thinners
Not all blood thinners react the same way with Ginkgo. Here’s what the numbers show:
| Blood Thinner | Interaction Risk | Recommended Action |
|---|---|---|
| Warfarin (Coumadin) | High | Avoid entirely |
| Aspirin | Moderate | Use with caution; monitor for bruising |
| Clopidogrel (Plavix) | Moderate | Discuss with doctor; avoid before surgery |
| Apixaban, Rivaroxaban (DOACs) | Moderate | Do not combine without medical approval |
| Acenocoumarol | Low | Monitor INR if used together |
Warfarin is the biggest red flag. The PLOS ONE study found that 18% of patients on DOACs who also took Ginkgo had a documented interaction. That’s a lot. And while aspirin seems safer in trials, real-world cases show increased bruising and bleeding, especially in older adults.
What Should You Do?
If you’re on a blood thinner and thinking about taking Ginkgo, here’s what to do:
- Stop. Don’t start. If you’re not already taking it, don’t begin unless your doctor says it’s safe.
- Check your current supplements. Look at your bottle. Does it say "EGb 761"? If not, you don’t know what you’re getting.
- Talk to your pharmacist. They see your full medication list. They’ll know if Ginkgo could clash with anything else you take.
- Stop Ginkgo before surgery. Whether it’s a dental extraction or knee replacement, stop it at least two weeks before. That’s the safest window.
- Watch for signs of bleeding. Unexplained bruising, nosebleeds that won’t stop, dark stools, or headaches could mean your blood is too thin.
And if you’re already taking Ginkgo? Don’t quit cold turkey. Talk to your doctor. Suddenly stopping could affect your circulation. But don’t keep taking it blindly either.
What About Other Herbs?
Ginkgo isn’t alone. Garlic, danshen, evening primrose, ginger, and turmeric also affect platelets. If you’re on a blood thinner, you’re playing with fire if you’re stacking these. One study found that nearly half of patients taking blood thinners were also using one or more of these herbs-and most didn’t tell their doctor.
That’s why the Institute for Safe Medication Practices lists Ginkgo as a high-alert herbal product. It’s not because it’s dangerous on its own. It’s because people don’t realize how many other things they’re mixing it with.
Bottom Line
The science is split. Some studies say Ginkgo is fine with blood thinners. Others say it’s a ticking time bomb. The truth? We don’t have perfect data. But we do have real people who bled out after taking both.
If you’re on a blood thinner, the safest choice is to avoid Ginkgo biloba. Not because every study says so-but because the cost of a mistake is too high. A brain bleed doesn’t come with a warning label. And your supplement bottle? It doesn’t know your medical history.
When in doubt, skip it. Talk to your doctor. And if you’re already taking it, don’t ignore it. That bottle on your shelf could be more dangerous than you think.
Can I take Ginkgo biloba if I’m on aspirin?
It’s not recommended. While some studies show no major interaction, real-world cases report increased bruising and bleeding in people taking both. Aspirin already thins your blood, and Ginkgo can make that effect stronger. If you must take both, talk to your doctor and watch closely for signs of bleeding like nosebleeds, dark stools, or unexplained bruising.
Is Ginkgo biloba safe with warfarin?
No. Warfarin and Ginkgo biloba are considered a high-risk combination. Even though some clinical trials found no effect, case reports show serious bleeding events-including brain bleeds-when the two are taken together. The Mayo Clinic and GoodRx both advise avoiding this combo entirely. Your INR levels can become unpredictable, and that’s dangerous.
How long before surgery should I stop Ginkgo biloba?
Stop Ginkgo biloba at least two weeks before any surgery or procedure involving bleeding risk-like dental work, colonoscopies, or joint replacements. The American Society of Anesthesiologists and multiple integrative medicine experts recommend this window to allow your platelets to return to normal function. Some doctors say 36 hours is enough, but two weeks is the safer standard.
Do all Ginkgo supplements have the same risk?
No. The research on safety mostly uses EGb 761, a specific standardized extract. Many store-bought supplements don’t contain this form-they’re weaker, inconsistent, or even contaminated. If your bottle doesn’t list "EGb 761" or the exact percentage of flavonol glycosides and terpene lactones, you can’t trust its safety profile. Stick to brands that disclose full ingredient specs.
Can I take Ginkgo biloba if I’m not on blood thinners?
If you’re not on any blood-thinning medication and have no history of bleeding disorders, Ginkgo biloba is generally considered safe for short-term use. But even then, watch for side effects like headaches, dizziness, or stomach upset. And if you ever start a blood thinner later-stop Ginkgo immediately and tell your doctor.
Rebecca Cosenza
November 21, 2025 AT 10:27Just stopped my ginkgo after reading this. No joke-I had unexplained bruising for weeks. Didn’t connect the dots until now. 🙃
swatantra kumar
November 22, 2025 AT 08:45Lmao so now we’re scared of trees? 🌳 In India we’ve been chewing ginkgo leaves since the 80s and our grandmas still dance at weddings. Maybe your meds are the problem, not the herb. 😎
Cinkoon Marketing
November 24, 2025 AT 06:06Actually, the EGb 761 extract is the only one with peer-reviewed safety data. Most store brands? Total crap. I checked 7 bottles last month-only 2 listed the exact flavonoid/terpene percentages. If your supplement doesn’t spell it out, you’re basically gambling with your platelets. 🤷♀️
robert cardy solano
November 24, 2025 AT 20:21Been taking ginkgo for 5 years with warfarin. Regular INR checks. No issues. But I also don’t take random supplements. I stick to one brand, one dose. Maybe that’s the difference? Not the herb. The chaos.
Pawan Jamwal
November 26, 2025 AT 19:26Western medicine always overreacts. In India, we use ginkgo, turmeric, ashwagandha-no problem. Your doctors are scared of natural things because they can’t patent them. 💪
Bill Camp
November 27, 2025 AT 14:51They’re lying to you. The FDA gets paid by Big Pharma. Ginkgo’s been used for 270 million years. You think some lab in New Jersey knows better than nature? Wake up. They want you dependent on pills that cost $500 a month. This is control. 🚨
Lemmy Coco
November 28, 2025 AT 04:59so i’ve been taking ginkgo with plavix for like 3 years? i didn’t know it was a thing. i’ve had a few nosebleeds but thought it was just dry air… should i stop??
rob lafata
November 29, 2025 AT 13:20You’re all missing the point. This isn’t about ginkgo-it’s about your pathetic inability to read a label. If you’re taking some $5 Amazon herb with ‘proprietary blend’ on it and then wonder why you’re bleeding out, you’re not a victim. You’re an idiot. And yes, I’m talking to you, Lemmy. 😈
Matthew McCraney
November 30, 2025 AT 00:27They’re watching us. The FDA, the pharmaceutical giants-they don’t want you to know ginkgo works better than warfarin. That’s why they bury the studies. I’ve got screenshots. I’ve got emails. They’re silencing the truth. Don’t trust anyone. Not even your doctor. 🕵️♂️
serge jane
December 1, 2025 AT 22:23It’s interesting how we treat natural substances as if they’re either pure magic or pure poison. The truth is somewhere in the messy middle. We don’t have perfect data because we don’t fund long-term observational studies on herbs-we fund trials for patents. So we’re left with case reports and theoretical risks. But humans aren’t variables in a lab. We’re complex. So maybe the answer isn’t ‘avoid’ or ‘take’ but ‘know your source, know your body, and listen to your pharmacist.’