Educational information, not medical advice — ask your doctor or midwife.
Yu Yu Liang is a mineral used in Traditional Chinese Medicine. It is limonite, a soft brown iron ore. Practitioners crush it to powder and use it as a drying, binding remedy.
Its classic use is for diarrhoea that has gone on for a long time. It is also used for heavy or ongoing bleeding from the womb and for vaginal discharge. It is a single mineral herb, but it is almost always used inside a mixed formula.
The honest evidence picture is thin. We found no controlled human trials of this mineral. Long traditional use tells you it has been valued for centuries, but it is not proof that it works.
Nobody has shown clearly how Yu Yu Liang acts in the body. In TCM theory it is heavy and astringent, meaning drying and binding. It is said to hold the bowel closed and stop leakage.
In chemical terms it is mostly iron oxide, the same family as rust, mixed with clay minerals. Clay minerals can soak up water and bind some toxins in test tubes. That work was done on clays in general, not on this mineral in people.
Whether any of this happens in the human gut has not been tested. Treat the mechanism as an idea, not a finding.
You will mostly meet Yu Yu Liang as a fine grey-brown powder, or as raw mineral lumps.
It is often calcined (heated red-hot) and then quenched in vinegar. This softens the mineral so it can be crushed and boiled.
It is rarely taken on its own. Most products are mixed formulas sold as granules, pills, or a decoction (a boiled water extract). In a decoction it is usually tied in a cloth bag and boiled first, before the plant herbs go in.
Yu Yu Liang appears in the Shen Nong Ben Cao Jing, a Chinese herbal text from around 200 CE. It sits in the mineral section of the classic drug lists.
The name means roughly "Yu's surplus grain", from an old legend about Emperor Yu. It is best known inside the formula Chi Shi Zhi Yu Yu Liang Tang, from the Shang Han Lun. That formula was written for diarrhoea that would not stop.
See a doctor if diarrhoea lasts more than two days, or if you see blood in the stool. Get help the same day for a fever, severe stomach pain, or signs of dehydration such as dizziness, dry mouth or very little urine.
See a doctor for any heavy or unexplained bleeding from the womb, rather than treating it yourself. Stop the mineral and seek advice if stools turn black and tarry, if you feel very tired, or if your skin or eyes look yellow.
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 Yu Yu Liang 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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