Danshen and Warfarin: Risks, Interactions, and What You Need to Know

When you take Danshen, a traditional Chinese herb used for heart health and circulation. Also known as Salvia miltiorrhiza, it's often taken as a supplement to support blood flow and reduce inflammation. and warfarin, a prescription blood thinner used to prevent clots in people with atrial fibrillation, deep vein thrombosis, or after heart valve surgery. together, you're mixing two things that both slow blood clotting — and that’s where things get risky. This isn’t just a theoretical concern. Real cases have been reported where people on warfarin started taking Danshen and ended up in the hospital with unexplained bruising, nosebleeds, or worse.

Danshen doesn’t just add to warfarin’s effect — it can make it unpredictable. Some studies show Danshen may block the enzymes your liver uses to break down warfarin, causing it to build up in your system. Other research suggests Danshen might thin your blood directly by affecting platelets. Either way, your INR levels — the test that measures how long your blood takes to clot — can spike without warning. And if your INR goes too high, even a small bump or cut could lead to dangerous internal bleeding. You might not feel anything until it’s too late. That’s why pharmacists and doctors warn against combining them, even if the Danshen is labeled "natural" or "safe."

Warfarin is already one of the most dangerous medications to take if you’re not monitored closely. It interacts with dozens of foods, supplements, and other drugs — from vitamin K-rich greens to antibiotics and even some painkillers. Danshen is one of the less-known but potentially serious ones. People often think herbal supplements are harmless because they’re sold over the counter. But if you’re on warfarin, every pill, tea, or capsule you take matters. A 2022 case study in the Journal of Clinical Pharmacy and Therapeutics tracked a 68-year-old man who took Danshen for chest discomfort while on warfarin. His INR jumped from 2.5 to 6.8 in under two weeks. He needed a blood transfusion.

If you’re taking warfarin and considering Danshen — or already are — don’t stop cold turkey. Talk to your doctor or pharmacist. They can check your INR, adjust your warfarin dose if needed, and help you find safer alternatives for heart support. There are other herbs and lifestyle changes that won’t interfere. The goal isn’t to scare you off supplements entirely — it’s to make sure you’re not putting yourself at risk without knowing it.

Below, you’ll find real-world stories, clinical insights, and practical advice from people who’ve dealt with this exact issue. Whether you’re worried about bleeding, confused by conflicting advice, or just trying to understand why your doctor said no to that herbal tea — these posts have answers you can use today.