Educational information, not medical advice — ask your doctor or midwife.
What is Artemisia afra? It is a tall, grey-green, strongly scented shrub from southern and eastern Africa.
Most people know it as African wormwood, umhlonyane, lengana or wilde-als. The leaves are brewed as a bitter tea or used as a steam inhalation for coughs, colds and fever.
It is a close cousin of sweet wormwood (Artemisia annua), the plant that gave us the malaria drug artemisinin. Artemisia afra does not contain artemisinin. That difference matters, and it is often blurred in marketing.
Here is the honest verdict on the evidence. Good human trials are almost absent, and one widely shared malaria trial was later retracted by the journal. Long and respected traditional use is not proof that a plant works, and it is not proof that it is safe.
The plant also contains thujone and camphor. Both can affect the brain and can trigger fits in large or repeated doses. So this is a herb to treat with respect rather than to sip daily for months.
How is it thought to work? Mostly through its aromatic oils, but almost all of the testing has been done outside the human body.
In test tubes, extracts slow the growth of some bacteria, including the bug that causes tuberculosis. Whether that happens in a person who drinks the tea is not established.
In laboratory tests, extracts also show some activity against malaria parasites. The effect is weak compared with real antimalarial drugs. No reliable human trial supports using the plant to treat malaria.
In animal studies, extracts have lowered blood sugar, eased pain and relaxed airway muscle. Animal results often fail to repeat in people, so treat these as leads, not findings.
The blocked-nose relief many people report is easy to explain. Hot steam and strong aromatic oils such as camphor and 1,8-cineole create a cooling, open feeling in the nose. That sensation is real, but it is not the same as clearing an infection.
How is it sold and used? Most often as the dried leaf, loose or in tea bags.
Common forms include:
- Dried or fresh leaf brewed as a hot, very bitter tea. - Steam inhalation made from the leaves in hot water. - Tinctures and liquid extracts in alcohol.
- Capsules and tablets of powdered leaf. - Cough syrups and mixed herbal blends. - Creams, oils and poultices for the skin.
- The concentrated essential oil, which is for scent use only.
Never swallow the essential oil. It is far stronger than the tea and the thujone and camphor in it can cause fits.
Strength is rarely stated on labels. Two packets of the same herb can differ widely in thujone content.
Where does its reputation come from? It is one of the oldest and most widely used medicinal plants in southern Africa.
Khoisan, Zulu, Xhosa, Sotho and Afrikaner households all recorded uses for it. It was taken for coughs, colds, flu, fever, sore throat and chest tightness.
Fresh leaves were rolled and placed in the nostrils for a blocked nose. Leaves were also steamed, used in baths, applied to the skin and brewed as a bitter tea.
Other recorded uses were for stomach cramps, worms, malaria-like fevers and to bring on a delayed period. That last use is a warning sign for anyone who is pregnant.
The plant remains a common home remedy in South Africa today, and it is sold in pharmacies and markets. This page describes that history; it does not recommend copying it.
Stop and get urgent medical help if you have a fit, twitching, confusion, a racing heart, or trouble breathing. Get help at once if a child who has inhaled or been given the plant becomes floppy, blue around the lips, or struggles to breathe.
See a doctor soon if your eyes or skin turn yellow (jaundice), if you have ongoing vomiting, or if you have dark urine.
Go to a doctor rather than reaching for the herb if you have a fever lasting more than two days, a fever after travel to a malaria area, chest pain, coughing up blood, or a cough lasting more than three weeks.
In South Africa it is sold widely as a herbal product and falls under SAHPRA rules for complementary medicines. In the UK, EU, US, Canada and Australia it is sold as a supplement or herbal tea, not as an approved medicine. The EU caps thujone levels in foods and drinks, so some products are limited or not permitted there.
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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