The traditional use of the medicinal plant Artemisia annua for the treatment of malaria entails the preparation of a tea infusion. In the scientific literature there have been some discrepancies on the quantity of the active principle, artemisinin, in the tea infusion. Due to these discrepancies, we decided to quantify artemisinin in tea infusions prepared according to different methods. We also studied the water solubility of pure artemisinin at room temperature and at 100 C and compared it to the solubility of artemisinin from the plant material. We found that the extraction efficiency is very sensitive to temperature and that efficiencies of above 90% can be reached. We also showed that the solubility of artemisinin is not improved by other components in the extract but that a supersaturated solution of artemisinin might be formed, which is stable for at least 24 hours.