Educational information, not medical advice — ask your doctor or midwife.
Achyrocline satureioides is a small South American herb with clusters of dry yellow flowers. It is widely known as marcela or macela. The dried flower heads are the part used, almost always as a tea.
It grows wild in southern Brazil, Uruguay, Argentina and Paraguay. People there have used it for hundreds of years for stomach upset, cramps and colds. Long use is not proof that it works, and it is not proof that it is safe.
The honest verdict on evidence is short. Human trials are few and small, so no health claim for this plant is settled. Nearly all of what is known comes from test tubes and animals.
It is sold as loose dried flowers, tea bags, tinctures and capsules. Most people who try it use it as a mild after-meal tea.
No one has shown in people how this plant acts, or that it acts at all.
In test tubes, extracts of the flowers mop up free radicals (unstable molecules that can damage cells). Lab work also suggests the flavonoids in it may damp down signals that drive swelling and pain. Whether this happens in a person drinking tea is not known.
In animal studies, extracts have relaxed gut muscle and eased spasm. That fits the old use for cramps and griping. It is still animal data, not proof in humans.
Some animal work points to a drop in blood sugar and in blood pressure. These findings are early and not confirmed in people. They matter mainly as a reason for care if you take drugs for those problems.
Lab tests show the essential oil slows some bacteria and fungi. Nothing shows this clears an infection in a person.
Dried flower heads for tea are the traditional and most common form.
You may also see: - Tea bags of the cut, dried flowers - Liquid tinctures in alcohol - Capsules of dried extract - Essential oil, for scent use only - The herb steeped in cachaça or other spirits, as a folk drink
In Uruguay and southern Brazil the dried plant has also been used to stuff pillows and scent linen. That is a household custom, not a treatment.
Marcela has long standing in the folk medicine of the South American grasslands.
Guaraní peoples and later gaucho communities used the flower tea for stomach pain, wind, poor digestion and period cramps. It was also taken for colds and taken as a calming drink at night. Some healers used it to bring on a late period, which is why pregnancy caution carries forward today.
In parts of Uruguay and Brazil the flowers were gathered in Holy Week, when they were thought to be strongest. The plant is listed by Brazil's health ministry among plants of interest for study in public health care. That listing marks it for research, not approval as a proven medicine.
Stop and get urgent help if you get swelling of the lips, face or throat, a spreading rash, or trouble breathing. Stop and see your doctor if you feel faint, shaky or sweaty, which can signal low blood sugar. See your doctor if stomach pain, cramps or indigestion last more than two weeks, come with weight loss, vomiting, black stools or fever. Those need a diagnosis, not a herbal tea.
In Brazil it is a recognised traditional herbal plant and appears on the health ministry's list of plants of interest for the public health system. In the United States and United Kingdom it is sold as a food supplement or herbal tea, with no approval to treat any illness. It is not a licensed medicine in the EU.
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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