Several species were used traditionally as medicinal qinghao, but only A. annua eventually proved to contain a sufficient amount of artemisinin.
虽然传统医学把不同品种的蒿都当作药用青蒿，但是后来发现只有a . annua含有足够的青蒿素。
3
WHO recommends combinations that contain derivatives of artemisinin — a substance extracted from the plant Artemisia annua — along with another effective antimalarial drug.