Educational information, not medical advice — ask your doctor or midwife.
Acmella oleracea is a small flowering plant in the daisy family. It is grown for its yellow-and-red button flower heads. Chewing a flower head makes the mouth tingle, buzz and go numb.
In Brazil the leaves are eaten as a vegetable called jambu. The plant is also sold as an extract in toothache drops, mouth rinses, oral sprays and anti-wrinkle creams. Other names include toothache plant, paracress, buzz buttons and electric daisy.
Here is the honest verdict on the evidence. The numbing and tingling effect in the mouth is real and easy to feel. Almost every other health claim rests on tradition and laboratory work, and long traditional use is not proof that something works or that it is safe.
The buzzing, numbing feeling comes mainly from spilanthol, an oily compound in the flower heads.
In laboratory and animal studies, spilanthol appears to damp down nerve signals that carry pain and touch. It also seems to cross skin and the lining of the mouth with ease. That fits the numbing people report within seconds of chewing a flower.
Other proposed actions are much less settled. In test tubes, extracts slow the growth of some bacteria and fungi. In animals, extracts have shown anti-inflammatory effects and have raised urine output.
None of that lab work tells you what happens in a person. Skin-care studies have suggested the extract may relax fine facial lines for a short time. The size and usefulness of that effect in daily life are not established.
So the fair summary is simple. One effect is obvious and local: it numbs what it touches. The rest is a set of leads, not findings.
You will meet this plant in four main ways.
As food: fresh jambu leaves and flower buds, cooked in soups and stews in northern Brazil. Whole dried flower heads are also sold as "buzz buttons" for drinks and garnish.
As a mouth product: toothache tinctures, numbing gels, mouthwashes, oral sprays and some chewing gums. These are usually made with an alcohol or oil extract.
As a skin product: creams and serums listing Acmella oleracea extract, sold for fine lines. These are cosmetics, not medicines.
As a supplement: capsules, powders and liquid extracts, sometimes standardised to a stated spilanthol level. Labels and strengths vary a great deal between brands.
The plant comes from the Amazon basin and has been grown across tropical South America for centuries. Rural healers used the chewed flower head on an aching tooth or sore gum.
That single use gave the plant its common name in many languages. In Brazil the leaves were, and still are, a kitchen vegetable in dishes such as tacacá.
Trade carried it across the tropics. Folk practice in India, parts of Africa and South East Asia later used leaf and flower preparations for mouth sores, throat pain, poor appetite and stomach complaints.
Nineteenth-century European pharmacy sold a tincture of the plant for toothache. These are records of what people did, not records of benefit, and none of them support treating yourself today.
Stop and get urgent help if you have swelling of the lips, tongue or throat, hives, or any trouble breathing. These suggest an allergic reaction.
Stop and call a doctor if numbness in the throat makes swallowing hard, or if you choke on food or drink.
See a dentist, not a herb, if a tooth hurts for more than two days, or if you have facial swelling, fever, or pus around a tooth.
See a doctor if dry mouth, poor appetite or mouth sores last more than two weeks. These can point to a problem that needs diagnosis.
In Brazil it is an ordinary vegetable sold in markets. In the United States it is sold as a food ingredient and a dietary supplement, and the FDA has not approved it as a medicine.
In the UK and EU the extract is widely used in cosmetics. Its status as a food or supplement ingredient varies by country, so check local rules.
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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