Educational information, not medical advice — ask your doctor or midwife.
Agoniada is the bark of Himatanthus lancifolius, a tree from Brazil. Healers in Latin America used it mainly for period problems. It is sold as dried bark, as a tincture and in capsules.
The tree belongs to the dogbane family. Its trunk gives a milky white sap called latex. The bark holds plant alkaloids, which are strong active compounds.
Here is the honest verdict. Nearly all we know comes from test tubes and animals. There are no good human trials, so long use by tradition is not proof that it works or that it is safe.
No one has shown what Agoniada does in the human body. Lab work points to its alkaloids, above all one called uleine.
In test tubes, uleine blocks an enzyme that breaks down acetylcholine, a nerve signal chemical. That could raise gut and muscle activity. Whether this happens at amounts people take is unknown.
In animal tissue, bark extracts made the womb contract. This fits the old use for bringing on a late period. It is also why pregnancy is a firm no.
In lab dishes, the bark slowed the acid pump of stomach cells. It also slowed Helicobacter pylori, a stomach bug. These are dish studies, not proof of ulcer relief in people.
Animal work also hints at effects on heart rate and blood vessels. None of it has been tested in human trials.
Agoniada reaches buyers mostly as dried bark and as liquid extracts.
Cut or powdered bark is brewed in water as a bitter tea. Alcohol tinctures are the most common liquid form. Dry extract capsules turn up in Brazilian herb shops.
Some products blend it with other "women's" herbs. Blends make it hard to know what you are actually taking.
Products are rarely tested for alkaloid content. Labels may skip the Latin name, which raises the risk of a mix-up.
The name agoniada is also used for other plants, including some Plumeria species. Check for Himatanthus lancifolius on the label before you buy.
Agoniada bark has a long record in Brazilian folk medicine. Writers in the 1800s listed it for painful and missing periods.
Healers also gave it for cramps, nerves, cough, asthma and fever. The name comes from a Portuguese word for distress.
It entered early Brazilian pharmacy texts as a bitter bark remedy, and its use spread through parts of South America. It is still sold in Brazilian herb markets today.
Stop taking it and get medical help the same day if you notice any of these.
Signs to act on: a slow, racing or fluttering heartbeat, fainting or near-fainting, chest pain, or trouble breathing.
Also stop and call a doctor for bleeding or cramping from the womb, repeated vomiting, severe stomach pain, a spreading rash, or yellow skin or eyes.
Go to an emergency department if a child swallows the bark, the tincture or the latex.
In Brazil, Agoniada bark is sold in herb shops and as a herbal product. It is not an approved medicine in the United States, the United Kingdom or the European Union, where it may appear as a supplement or not at all.
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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