Pure artemisinin or Qinghaosu, the active constituent of the herb Artemisia annua (sweet wormwood). Good quality Artemisia annua contains 0.3-0.5% artemisinin, so pure artemisinin provides hundreds of times more of the active constituent artemisinin than the whole herb itself. Allergy Research Group introduced artemisinin to the U.S. market more than a decade ago. Allergy Research Group does independent potency assays on every batch (using HPLC), and independent tests verify its effectiveness. Allergy Research Group artemisinin is minimum 98.5% pure, and does not contain thujone.