How Artemisinin Was Discovered: From Plant to Medicine 2026

Artemisinin was discovered in 1971 and 1972 by Tu Youyou and her colleagues at the Institute of Chinese Materia Medica in Beijing, who isolated it from the leaves of sweet wormwood (Artemisia annua) after abandoning boiling-water extraction in favour of a cold ether method. Knowing how artemisinin was discovered means following one failed laboratory technique, one very old Chinese text, and a short window of field testing in the early 1970s.

The story matters beyond pharmacology. It is the clearest modern case of a documented traditional preparation method pointing a research team toward a compound that screening programmes had missed for decades, and it changed how Chinese state research treated old medical texts.

The date needs a small clarification up front. Tu’s team produced a neutral extract of sweet wormwood that cured malaria in 1971, and the pure compound artemisinin (qinghaosu) was isolated and characterised in 1972. Many sources say simply “1972”, and both dates refer to the same project at different stages.

What Is Artemisinin and Why Does Its Discovery Matter?

Artemisinin is a chemical compound, not a plant. It is a sesquiterpene lactone with an unusual endoperoxide bridge, and it is extracted from the leaves of Artemisia annua, a member of the daisy family and a close relative of ragweed, chamomile and tarragon.

Its importance comes from what it does. Artemisinin clears blood-stage malaria parasites faster than any earlier antimalarial, including chloroquine, which is why the World Health Organization places artemisinin-based combination therapies at the front of its treatment guidance. The discovery turned a plant remedy that had been described for roughly sixteen centuries into a modern medicine.

Because the name gets mixed up constantly, here is a quick disambiguation:

Term	What it is	Role
Artemisia annua	A plant, also called sweet wormwood or qinghao	The botanical source; the leaves contain artemisinin
Artemisinin (qinghaosu)	A single purified molecule	The active ingredient; the compound discovered in 1972
Dihydroartemisinin	A derivative made from artemisinin	Base chemical for the semi-synthetic medicines
Artesunate	A water-soluble derivative	Oral and intravenous treatment, including severe malaria
Artemether	A more fat-soluble derivative	Oral and injectable formulations, widely used in Africa
Ivermectin	An unrelated anti-parasitic drug from Streptomyces bacteria	Antiviral claims around it were never supported; no connection to artemisinin

That relationship between plant and molecule is not unusual in drug history. Quinine came from cinchona bark, salicylic acid from willow bark, and morphine from the opium poppy, all long before a laboratory understood what it was holding. Artemisinin is the most recent and by some measures the most successful of that list, and it is the clearest case where a traditional preparation detail, not a screening programme, set the research direction.

How Artemisinin Was Discovered in Sweet Wormwood

The discovery came out of a state research programme, not a single laboratory hunch. China launched Project 523 on 23 May 1967 to find a treatment for chloroquine-resistant malaria spreading through the Vietnam War. Tu Youyou, then 39, took over the malaria group in 1969 and inherited a screening effort that had already tested hundreds of thousands of compounds without success.

She spent time in the field on Hainan Island, watching malaria cases directly, and in 1971 she re-read the classical Chinese medical literature. The decisive passage was in Ge Hong’s Handbook of Prescriptions for Emergencies, compiled around the fourth century, which described taking sweet wormwood in a cup of water and drinking the juice.

The first extraction attempt used the lab’s normal method: boil the plant in water. It failed. The team then tried diethyl ether, which boils at about 35 degrees Celsius and dissolves the compound without destroying it. That low-temperature extract wiped out malaria parasites in mice and monkeys, then in people.

Tu and two colleagues tested the neutral extract on themselves first. It worked. The same extract was then given to patients on Hainan, and 21 recovered, which is the clinical result most often cited from that period.

The Traditional Knowledge Behind the Discovery

What made the breakthrough possible was a detail in the old text that read like a footnote. Ge Hong’s instruction was to wring out the juice of one handful of fresh plant in a cup of water and drink it all. That is an unheated preparation, not a simmered decoction, and the twentieth-century laboratory assumption was that every plant extract had to be decocted in boiling water.

The researchers were not verifying an ancient claim wholesale. They took one specific preparation instruction as a lead, tested it properly, and discarded the rest. That distinction matters, because broad claims about traditional remedies rarely survive laboratory scrutiny, while a single well-recorded preparation detail sometimes points directly at the right molecule.

What Traditional Harvesters Already Knew About the Plant

Harvesters who used qinghao long before modern laboratories existed also carried practical knowledge that never appeared in pharmacopoeias. Collectors reported that artemisinin content varies sharply between plants in the same field, between young and mature leaves, and between morning and afternoon harvests.

Seasonality and flowering stage matter too. This is exactly the kind of local, plant-specific knowledge ethnobotanical work tries to document, and it explains why a plant can be useless in one harvest and potent in the next. It also explains why commercial production today relies on controlled cultivation rather than wild collection.

How Artemisinin Was Discovered: Inside the Chinese Research Project

Project 523 ran through one of the most disruptive political periods in modern Chinese history, and its secrecy shaped how quickly results reached the outside world. The sequence below is the documented path from state priority to global medicine.

Year	Event	Why it mattered
1959 to 1962	Tu Youyou trained full time in traditional Chinese medicine alongside her pharmacology degree	Gave her the ability to read classical sources critically
1967	China launched Project 523 on 23 May	A national effort against chloroquine-resistant malaria
1969	Tu appointed to lead the malaria research group at age 39	Put a pharmacologist with TCM training in charge
1969 to 1970	Field research on Hainan Island	Direct observation of patients and local plant use
Before 1971	Large-scale screening of synthetic and plant candidates	Widely cited as more than 240,000 compounds with no result
1971	Re-reading Ge Hong’s text, then cold ether extraction	A neutral extract cured malaria in animals and humans
1972	Pure artemisinin isolated and characterised	The active compound was finally identified
1977 and 1979	Chinese-language publications	Results circulated mainly inside China
1979	English-language publication	The wider scientific world could evaluate the work
1981	WHO, World Bank and UN meeting in Beijing	International bodies assessed the compound formally
2000s	WHO recommends artemisinin-based combination therapy	ACT became first-line treatment worldwide
2015	Nobel Prize in Physiology or Medicine awarded to Tu Youyou	Formal recognition, 43 years after the isolation

Why Mass Screening Alone Had Not Found It

The failure before the success is the part most summaries skip. Screening programmes across several countries had tested a very large number of compounds, and the Chinese effort alone is commonly credited with more than 240,000. Randomised screening of plant extracts had produced nothing usable, because the active compound is present at low concentration and unstable under the standard extraction conditions.

That is the wider lesson about plant drugs, and the reason summaries of how artemisinin was discovered so often skip past the failed boiling pot and go straight to mass screening: a plant can hold a powerful molecule and still look useless to a laboratory using the wrong solvent or the wrong temperature.

How Did Researchers Prove Artemisinin Worked?

Evidence accumulated in stages, each one ruling out a simpler explanation. In laboratory testing, the extract killed blood-stage Plasmodium parasites at concentrations that were not toxic to the host cells, which is what separated a real antimalarial from a general toxin.

Animal work followed in mice and monkeys, where the treatment cleared parasites and animals recovered. Human evidence came next, beginning with Tu and two colleagues dosing themselves, then with hospital patients on Hainan Island who recovered after treatment with the neutral extract.

The chemical work then explained the effect. Inside the parasite’s digestive vacuole, haemoglobin is broken down and the released iron sits in a toxic heme-ferriprotoporphyrin IX complex that the parasite normally converts to harmless haemozoin. Artemisinin appears to interfere with this process, generating reactive species that damage the parasite from inside. Because it acts inside the parasite’s own digestive vacuole rather than on a human target, artemisinin clears blood-stage parasites far faster than chloroquine did.

Tu Youyou described her own first full clinical course in two patients at the start of 1972, using the pure compound rather than the extract. Their fevers broke within days and their blood films cleared.

Why Did the Discovery Lead to Artemisinin-Based Medicines?

Artemisinin on its own was not the finished medicine. It is poorly soluble, it breaks down quickly in the body, and used alone it selects for resistance. The short clearance window, roughly two to three days, is exactly the setting in which resistant parasites can survive and spread, and resistance markers have since been confirmed in the Greater Mekong subregion.

Chemists fixed the first problem by making derivatives. Dihydroartemisinin, artesunate and artemether are semi-synthetic modifications of artemisinin that are more stable and can be formulated for oral, injectable or intravenous use. Intravenous artesunate became the standard treatment for severe malaria in hospital.

The second problem was solved with combination therapy. Pairing an artemisinin derivative with a longer-acting partner drug from a different chemical class means any parasite surviving the fast artemisinin phase is still exposed to the partner. Two drugs acting by different mechanisms cut the probability that a single resistant mutant survives to repopulate, and WHO now recommends artemisinin-based combination therapy for uncomplicated falciparum malaria.

Today artemisinin is not only used as a medicine. Artesunate and other derivatives are being studied for conditions far from malaria, including schistosomiasis and cardiac fibrosis, work that owes its head start entirely to a drug that was already approved and stocked worldwide.

Who Should Receive Credit for Discovering Artemisinin?

Tu Youyou received the 2015 Nobel Prize in Physiology or Medicine, and she was the central figure. She led the group that chose the cold extraction, ran the tests, and published the results. The award itself is unusual in recognising only one scientist for a discovery made inside a state programme.

The wider credit matters too. Project 523 involved close to 200 researchers across the Academy of Traditional Chinese Medicine, provincial institutes in Shandong and Yunnan, and the Shanghai Institute of Organic Chemistry, where the chemical characterisation work happened. Ge Hong, writing around the fourth century, supplied the observation that unlocked the search. And farmers and herbal collectors had sustained the plant’s use in a far corner of tropical China for centuries.

A second, quieter contribution came from North Vietnamese scientists and from Chinese military medicine, who shared traditional plant remedies such as Artemisia apiacea and A. anomala during the war effort. Not all of those leads produced artemisinin, but the collaboration pointed Chinese researchers at the right genus.

For further reading, the primary sources are Tu Youyou’s own 2011 account in Nature Medicine, “The discovery of artemisinin (qinghaosu) and gifts from Chinese medicine”; Su and colleagues’ 2015 review on the discovery and the Nobel Prize in the same journal’s family of PMC articles; Louis Miller’s 2011 narrative in Cell; and the Nobel Foundation’s Tu Youyou biography.

Frequently Asked Questions

Conclusion

The discovery of artemisinin moved through five stages: a plant remedy recorded in a fourth-century Chinese medical text, a national research programme that failed at scale, a switch from boiling water to cold ether, animal and human proof, and finally a pure compound that became the parent of today’s antimalarial derivatives.

What a reader can take from it is straightforward. Traditional knowledge is often dismissed as noise, and here it supplied the one observation that hundreds of thousands of screened compounds could not. The right next step for a suspected malaria infection is a diagnostic test and current WHO-recommended treatment from a clinician, never sweet wormwood tea or juice brewed at home.