Alstonia boonei

What is Alstonia boonei?

Alstonia boonei is a tall tree from the forests of West and Central Africa. The bitter bark is the part most often used. The leaves and the milky white sap are used too.

Common names include stool wood, cheesewood and God's tree. In Ghana it is called onyame dua. Yoruba speakers in Nigeria call it ahun or awun.

Healers have used the bark for fever, malaria, pain and swelling for generations. It is still sold as bark pieces, powders and mixed herbal syrups across the region.

Most research is in test tubes and animals, not in people. There are no good human trials. Long traditional use is not proof that a plant works, and it is not proof that it is safe.

The most important practical point comes first. Malaria is a serious illness that can kill within days. If malaria is a possible cause of a fever, get a test and a proven malaria drug.

How does Alstonia boonei work?

No one has shown how this bark works in people. Everything below comes from lab or animal work.

The bark holds bitter alkaloids, mainly echitamine. In test tubes, bark extracts slow the malaria parasite Plasmodium falciparum. Whether that happens in the blood of a person at a safe dose is not established.

In rats and mice, bark extracts have lowered fever and reduced swollen paws. Some animal work compares the effect to common anti-inflammatory drugs. These results do not prove the same thing happens in humans.

Animal studies also report lower blood sugar and lower blood pressure after bark extracts. In rodent tissue, extracts have made the uterus (womb) contract. That matches the old use in childbirth, and it is why pregnancy is a firm no.

Alkaloid levels change with the tree, the season and the piece of bark. So two batches can act very differently. That is one reason human results are hard to predict.

What forms does Alstonia boonei come in?

The bark is the main form in trade, usually as dried chips or powder.

You may meet it as:

- dried bark pieces, sold loose by weight - bark powder, loose or in capsules - a water decoction, the old home method of simmering bark - alcohol tinctures and liquid extracts - mixed herbal "fever" or "malaria" syrups sold in West Africa, where it is one of several plants - fresh latex (sap) or leaf pulp, put on the skin

Mixed syrups are hard to judge. You cannot tell which plant is doing what, or how much of each is there.

The wood is also used for stools, carving and plywood. That trade has nothing to do with the medicinal use.

Where it comes from:

Alstonia boonei was one of the best known fever plants of West and Central Africa. Records of its use go back to the 1800s and earlier.

In Ghana the tree was treated as sacred and called onyame dua, the tree of God. It was linked with shrines and with carved stools. Felling it often involved ritual.

Traditional healers used bark decoctions and bark powder for:

- fever and what was called malaria fever - rheumatic pain and aching joints - care of women after childbirth, and to help milk flow - snakebite, arrow wounds and toothache - intestinal worms - asthma and chest complaints

The bark appears in modern African herbal pharmacopoeias, including monographs from Ghana and Nigeria. A monograph records how a plant has been used and how to identify it. It is not a finding that the plant treats disease.

This page records that history. It is not advice to copy it at home.

What does Alstonia boonei help with?

• Fever and suspected malaria: This is the classic use across West Africa. Bark decoctions were drunk at the start of a fever. In test tubes, bark extracts slow the malaria parasite. In rodents, extracts have lowered fever. There are no proper human trials showing that it clears malaria. Using it instead of a tested malaria drug is dangerous. Get a blood test and treatment from a clinic.
• Joint and muscle pain: Healers used the bark and bark soaks for aching joints and back pain. In rats, extracts have eased pain responses and reduced swelling. The size of the effect in people is unknown. No trial has compared it with a standard pain reliever (analgesic).
• Swelling and inflammation: Animal studies are the main support here. Bark extracts reduced paw swelling in rats. Some of the plant fats in the bark, such as lupeol, calm inflammation in cell studies. Whether a cup of bark tea does this in a human body has not been shown.
• Care after childbirth: Bark was widely given to women after birth, and sometimes to speed up labour. It was also used to help milk flow. Rodent tissue studies show the extract can make the womb contract. That is a reason for caution, not comfort. Do not use it in pregnancy or when breastfeeding.
• Asthma and chest complaints: Bark and leaf preparations were used for cough, wheeze and chest tightness. Human evidence is absent. Asthma attacks can be fatal and need inhalers or other prescribed treatment. Herbal tea is not a substitute.
• Skin sores and wounds: The milky sap and crushed leaves were put on sores, ulcers and snakebite wounds. In lab tests, extracts slow the growth of some bacteria and fungi. Whether that works on real skin is not established. Raw sap on an open wound also carries an infection risk.
• Intestinal worms: Bitter bark drinks were a traditional worm remedy in several regions. Some lab work shows activity against worms outside the body. There is no human trial. Proven, cheap worm tablets exist and are far more reliable.

Which foods are rich in Alstonia boonei?

This is a tree bark, not a food. It is not found in any normal diet, and no food supplies the same compounds.

What are the side effects of Alstonia boonei?

• Nausea and vomiting
• Stomach pain and cramps
• Diarrhoea
• Loss of appetite from the strong bitter taste
• Dizziness or feeling faint, from a drop in blood pressure
• Shakiness and sweating, which can signal low blood sugar (hypoglycaemia)
• Headache
• Cramping of the womb
• Skin rash in people who react to the sap
• Yellow skin or eyes and dark urine, which can signal liver strain

Good to know:

Stomach upset is the effect people report most. It usually settles after stopping.

Serious harm is reported rarely. But safety reporting is weak in the places where the bark is used most, so rare may mean under-counted.

The real worry comes from animal work. High or repeated doses damaged the liver and kidneys in rodents. Treat yellow eyes, dark urine or severe stomach pain as urgent.

How much Alstonia boonei should you take?

• Recommended daily: There is no agreed dose, because no human trial has set one. Products sold in West Africa carry their own label amounts. These are often a spoonful of bark decoction or one capsule of bark powder, taken a few times a day. Those numbers come from custom and from the maker, not from research. Strength varies a great deal between batches. The same spoonful can be mild from one tree and strong from another. Nothing here is an amount for you to take.
• Best time of day: No study shows that timing matters. The bark is very bitter, so many people take it after a meal.
• With or without food: Food may help. Taking bitter bark on an empty stomach often causes nausea and stomach pain.
• Time to effect: Honest answer: unknown. Tradition expected fever to ease within a day or two. It may do nothing at all. If a fever is still there after 48 hours, that is a reason to see a doctor, not to take more.
• How long to take it: Traditional use was short. Bark drinks were taken for a few days during a fever, then stopped. Long daily use has not been studied in people. In rodents, repeated high doses damaged the liver and kidneys. That makes open-ended daily use a bad idea.