Common supplements may heighten bleeding risk during surgery, Polish study finds

Editor's Note

Many widely used supplements and herbal remedies can increase bleeding risk during surgery and should be stopped in advance, according to researchers at Wrocław Medical University. The findings highlight a gap in perioperative safety practices, The Am-Pol Eagle September 18 reports.

The study, led by the university’s Department of Dietetics and Bromatology and the Department of Pharmacognosy and Herbal Medicine, analyzed active substances in supplements and herbs that interfere with blood clotting. The researchers reported compounds in popular preparations such as garlic, cinnamon bark, ginkgo biloba, ginseng, ginger, turmeric, and St. John’s wort may act as anticoagulants or fibrinolytics when consumed in supplement form. While safe in culinary use, these concentrated extracts can significantly elevate bleeding risk, particularly when combined or taken with prescription drugs.

Joanna Pieczyńska, PhD, noted both patients and clinicians often underestimate the problem. She pointed out that up to 70% of patients fail to disclose supplement use to their physicians, and few physicians actively inquire. “Doctors often lack this awareness as well,” she said in a press release, noting products such as garlic or cinnamon are frequently assumed to be harmless because they are natural. In reality, garlic inhibits platelet aggregation, and cinnamon contains coumarins that antagonize vitamin K, both of which compromise coagulation.

Researchers categorized supplement risks into three groups: coumarins, present in sweet clover, cinnamon, and angelica; salicylates, found in willow bark and aloe vera; and fibrinolytic agents such as ginkgo, ginseng, ginger, turmeric, garlic, and St. John’s wort. They emphasized these substances can complicate intraoperative hemostasis and extend postoperative recovery.

The outlet reports the American Society of Anesthesiologists already advises discontinuing supplements and herbal products at least 2 weeks before planned procedures, even if mechanisms are not fully defined. The Polish team argues similar caution is urgently needed in Poland, where few patients seek professional guidance when purchasing supplements.