Asteraceae
Artemisia annua
Sweet wormwood · Qing hao · Annual wormwood
- Part used
- leafaerial
- Native range
- Temperate Asia, principally China; naturalised widely
- Morphology
- A tall aromatic annual to two metres, with finely divided ferny leaves and inconspicuous yellow flower heads.
What is in it
Evidence
Artemisinin and its derivatives, given as artemisinin combination therapy, are the first-line treatment for falciparum malaria worldwide. The World Health Organization advises against using the plant material or herbal teas, because uncontrolled sub-therapeutic dosing accelerates resistance.
Safety
The isolated drug is well tolerated. The concern with the plant is not toxicity but resistance: partial doses from teas and unstandardised preparations select for artemisinin-resistant parasites, which is now a documented and serious global problem.
Regulatory: Artemisinin derivatives are prescription antimalarials. WHO explicitly discourages herbal Artemisia preparations for malaria treatment or prevention.
How the traditions classify it
Three systems, rating the same plant. Where they disagree, none of them is correcting the others — they are separate frameworks that arrived at their categories independently.
Historical use
In the Chinese materia medica for well over two thousand years. Ge Hong recorded a preparation for intermittent fevers in the fourth century CE, specifying that the herb be soaked in cold water and the juice wrung out.
Recorded as history and attributed where possible. Long use establishes that a plant was widely used, not that it worked, and not that it was safe.
What it is taken for, and who says so
Sold in wellness markets as a tea or extract for immune support and, in some quarters, as an antimalarial or anticancer agent — claims the World Health Organization has warned against because the plant is not a substitute for the isolated drug.
Recorded because it is what people believe, not because it is what the plant does. Whether any of it holds up is the Evidence section above, and the two frequently disagree. A sincere account of feeling better is compatible with the plant doing nothing — see the placebo effect.
Worth knowing
Tu Youyou's work is the strongest single argument that traditional literature is worth reading carefully, and the strongest argument that reading it is not the same as using it.
Her team screened hundreds of traditional recipes and the extracts kept failing. She went back to Ge Hong's fourth-century line and noticed the method: cold water, not the standard hot decoction. Heat was destroying the compound. Changing the extraction produced the result, she took the first dose herself, and she received the Nobel Prize in Medicine in 2015.
Then the same organisation that celebrates the discovery tells people not to drink the tea — because a partial dose is worse than none. Both positions are correct, and holding them together is the whole discipline.
Nomenclature verified against GBIF backbone taxonomy.