Educational information, not medical advice — ask your doctor or midwife.
Daegye is the dried root and above-ground part of Cirsium japonicum, a thistle also called Japanese thistle. In Korean herbal medicine it is a single drug, meaning it is one plant used on its own rather than a fixed formula. Its classic job is to slow bleeding and to "cool the blood" — an old term for calming conditions seen as hot, red and bleeding.
Healers have given it for coughing or vomiting blood, blood in the urine, nosebleeds, heavy menstrual bleeding and bleeding piles. It is also applied to the skin for sores and small wounds. A long record of use tells you people trusted it; it is not, on its own, proof that it works, and that difference holds for everything on this page.
Evidence verdict: a long-standing staple of Korean and East Asian herbal practice, but the published science is almost entirely laboratory and animal work, so the evidence grade here is low.
Nobody has shown clearly how daegye works in people. What follows is the best current thinking, not settled fact.
Laboratory work suggests its flavonoids (plant pigments with antioxidant activity) can calm inflammation and may act on small blood vessels. Animal studies have reported shortened bleeding times and some lowering of blood pressure and blood sugar. Animal results often do not carry over to humans.
Traditional Korean theory explains it differently: daegye is said to clear heat from the blood and stop reckless bleeding. That is a description of a pattern a practitioner sees, not a measured biological mechanism.
Daegye is most often sold as dried, cut root or whole herb for making a decoction — a strong tea made by simmering the herb in water.
Other forms you may meet:
Granules or powdered extract, dissolved in hot water.
Capsules or tablets of dried extract.
Charred daegye (daegye-tan), toasted until blackened, traditionally preferred when the aim is to slow bleeding.
Fresh juice or a poultice of the crushed fresh plant, used on the skin in folk practice.
Daegye appears in Korean medical texts including the Donguibogam (1613) and in the wider East Asian materia medica, where it is paired with sogye (small thistle, Cirsium setosum). Its role has been stable for centuries: bleeding that is seen as hot and sudden. Korean, Chinese and Japanese practice all use it, and it remains a listed herb in the Korean Pharmacopoeia.
Get emergency help now if you cough up or vomit blood, pass black tarry stools, bleed heavily and cannot stop it, or feel faint, cold and sweaty with bleeding. Go to hospital if you develop swelling of the lips or tongue, a spreading rash or trouble breathing after taking it.
See your doctor within a few days if you notice blood in your urine, bruises appearing for no reason, yellowing of your skin or eyes, dark urine, or if your periods have become much heavier. Also check in if you feel dizzy or faint, which may mean your blood pressure or blood sugar has dropped too low.
And tell your doctor or pharmacist that you are taking daegye before any surgery or any new prescription.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
Reviewed by the HealisticMD editorial team How we grade evidence →
The published evidence for daegye is weak or absent. That usually means no controlled trial has tested it, not that a trial found it ineffective — the two are different, and we grade only what has been published.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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