The cinchona alkaloid quinine and its d-diastereomer quinidine have been used for over 350 years for the treatment of malaria (Rocco, 2003). Although the bark of the cinchona tree had been used as a traditional medicine for the relief of fever by Andean healers, it was first used in Europe for ague (malaria) in the 17th century by Cardinal Juan de Lugo, and later by Robert Tabor, who successfully treated King Charles II (Bruce-Chwatt, 1988). It remained the sole effective antimalarial agent until World War I, when declining stocks of quinine led to the development of synthetic anti-malarials.