Educational information, not medical advice — ask your doctor or midwife.
Stool wood is the bark of Alstonia boonei, a tall forest tree of West and Central Africa. Healers there used the bark for fever, malaria, pain and swollen joints. It is still sold in markets as bark chips, bark powder, or a bitter boiled bark water.
The tree is called onyame dua or nyamedua in Twi, and ahun in Yoruba. The soft wood was carved into stools and shrine objects, which gave it the English name. Some books also call it cheese tree or pattern wood.
Here is the honest verdict. Good human trials are almost absent, so we cannot say the bark treats any illness. Long traditional use is not proof that it works, and it is not proof that it is safe.
Almost everything known about how it acts comes from lab dishes and animals, not from people.
In test tubes, bark extracts slow the growth of the malaria parasite. Whether that happens in a person who drinks the bark water is not known.
In rats and mice, extracts have lowered fever and reduced pain signs and swelling. The bark's alkaloids and triterpenes are the likely drivers. Animal results often do not carry over to humans.
In animal work, echitamine, one of its alkaloids, can drop blood pressure and act on the heart. Animal tissue studies also report effects on the muscle of the womb. These findings are a warning as much as a promise.
Dried stem bark is the main form you will meet.
It is sold whole, in chips, or ground to a powder. Sellers often supply a boiled bark water, called a decoction. Soaks in local gin or palm wine are used in some areas.
The fresh latex and the leaves are used in places too. Bark is sometimes mixed into multi-herb market blends. In a blend, you cannot tell how much alstonia is in the cup.
A few shops and websites sell capsules or tinctures. These are rarely standardised. The label will not tell you the alkaloid strength.
The tree held a high place in Akan belief. The name onyame dua means "God's tree". Its light wood was carved into stools, drums and shrine pieces.
Healers in Ghana, Nigeria, Cameroon and Côte d'Ivoire used the bark for fever and malaria. It was also given for aches, joint pain, asthma and cough.
Birth attendants used it after childbirth to help push out the afterbirth. It was applied to snakebite wounds and skin sores as well. These were recorded practices of trained local healers, not a guide for home use.
Stop and see a doctor if you feel dizzy, faint, or notice your heart beating slowly or unevenly.
Get urgent care for yellow eyes or skin, dark urine, very little urine, bad stomach pain, or repeated vomiting.
Go to hospital now for a high fever that will not settle, confusion, fits, trouble breathing, or swelling of the face, lips or tongue.
In the United States, the United Kingdom and the European Union, Alstonia boonei is not approved as a medicine and is not a common supplement. In Ghana and Nigeria it is sold freely as market bark, and finished herbal products are meant to be registered with the national regulator (FDA Ghana or NAFDAC).
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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