Yunnan Baiyao: What It Is, Traditional Use and Safety Issues

What it is

Yunnan Baiyao is a Chinese patent medicine from Yunnan province that has been used as a hemostatic (bleeding-control) drug for nearly 100 years. [1] Reviews describe it as widely used in China for bleeding, inflammation, pain and wound healing, and it is made as a powder, capsules, tincture and toothpaste. [2] Traditionally the powder is applied to wounds or taken by mouth for internal bleeding. [2]

This is information only. Heavy bleeding, coughing up blood or vomiting blood is an emergency; in the US, call 911.

The secret formula

The full recipe is not public. Reviews say the formula is a protected state secret in China. [2] Panax notoginseng (sanqi) is named as a core component. [2] Beyond that, the published picture is incomplete and has caused controversy.

• A 2021 review says a US company's 2002 attempt to market the tincture as a dietary supplement was rejected by the FDA. The papers filed listed components, but not the poisonous herb Cao-wu (Aconitum), even though Chinese medicine circles widely accept it is part of the formula. The review therefore doubted the listed prescription's accuracy. [3]
• A veterinary commentary quoting a 2014 Beijing Review report says the manufacturer admitted the product contains aconitum, which can cause numbness of the mouth and limbs, nausea, breathing difficulties and heart rhythm problems if used improperly. The company said its processing greatly reduces the toxicity, and still did not disclose the full formula. [4] That source is commentary, so treat the detail as secondary.
• One herb company, Mayway, stopped selling the oral form in June 2013, citing reports of injuries, possible contamination and undeclared ingredients. [4]
• Researchers note that the secrecy means active ingredients are not fully clarified. [3]

For the herb behind aconite concerns see Chinese herbs with known safety concerns.

What research shows

1. Bleeding and ulcers overall

   Serious

   A 2014 meta-analysis of 55 studies (5,150 patients) found benefits, but heterogeneity and possible publication bias prevent firm conclusions, and two results were unstable when high-risk trials were removed. [5]

   Insufficient evidence

2. Blood loss in jaw surgery

   Unclear

   A double-blind, placebo-controlled trial of 87 patients found less blood loss with Yunnan Baiyao capsules before surgery (about 330 mL against 420 mL). [1] It did not follow recovery or long-term outcomes. [2]

   Promising but limited (one trial)

3. Coughing blood, added to usual care

   Unclear

   A meta-analysis of 13 trials (1,379 patients) found better efficacy than usual treatment alone. [6]

   Promising but limited

4. Diabetic foot ulcers

   Unclear

   A 2026 open-label trial with blinded assessment (117 completers) found faster wound-area reduction at 2 weeks (61.5% powder, 70.0% ointment, 46.4% control); complete healing at 8 weeks did not reach statistical significance. [7]

   Promising but limited

5. Pain, cancer and other uses

   Unclear

   A 2025 review says evidence for pain relief comes mainly from animal experiments and clinical data are limited. [2]

   Preclinical

Yunnan Baiyao is not a substitute for medical care of serious bleeding or for wound care in diabetes.

Safety

• Aconite alkaloids. Toxicology studies attribute the formula's toxicity mainly to alkaloids from Cao-wu. [3]
• Reported reactions. A monitoring study of 31,556 Chinese users of the capsule found an adverse drug reaction rate of 1.17% (intention-to-treat), mostly mild; the most frequent were nausea and vomiting. [8] The surgery trial recorded no allergic reactions or clotting events. [1]
• Medicines and surgery. Proper evidence not found: my PubMed search for interactions with warfarin or other blood thinners returned nothing relevant. Because it is used to affect bleeding, tell your surgeon, dentist and pharmacist before using it. See supplements before surgery and how interactions work.
• Pregnancy. The human sources I read did not cover pregnancy; ask a clinician. See pregnancy and breastfeeding.
• Quality. Because the formula is secret, you cannot check a product's contents against a published recipe. See buying Chinese herbs safely. For the bigger picture see Chinese herbal medicine.