Ephedrine is an alkaloid obtained from Ephedra sinica Stapf., E. equisetina Bunge, and other species of Ephedra (Fam. Ephedraceae), but is usually produced synthetically. Ephedra or Ma-Huang is the entire plant or the overground portion of Ephedra sinica grown in China. In Chinese characters »Ma« means astringent and »Huang« means yellow, probably referring to the taste and colour of the drug. It has been used as a medicine in China for more than five thousend y ears. Its use in modern medicine began with the recent discovery of the valuable properties of ephedrine. Allied Plants -in addition to Ephedra sinica, the source of Ma-Huang, and E. equistina, the chief source of the alkaloid, E. distachya L. also yields ephedrine. These plants grow in northern China, India and in Europe. Ephedra sinica Stapf. is a low shrub, 60 to 90 cm high, growing in sandy or clay soil chiefly in northern Hopeh. E. sinica y ields 0.44 to 1.35% of total alkaloids of which 75-85% represents ephedrine and 15 to 25% pseudoephedrine. The drug is best gathered in autumn when its alkaloidal content is greatest. This plant is known commercially as Tsaopen Ma-Huang. Ephedra equisetina Bunge is a low woody Asiatic shrub, 1 to 2 m in height with a long cronical root from which arises a much · branched stem. E. equisetina yields from 0.6 to 1.75% of total alkaloids of which 85 to 90% is ephedrine, and 10 to 15% pseudoephedrine. This plant is known commercially as Mupen Ma-Huang. Ephedra distachya L. is a low, rigid shrub (38 cm), growing along the Hopeh-Shansi border and in Europe, in central Mediterranean countries. The plant contains both ephedrine and pseudoephedrine, but the total alkaloid y ield is about 30% less than E. sinica. It is collected in central China and Europe and exported chiefly from Tien-tsin and Spain. Ephedra gerardiana Wall., a dwarf species 15 to 60 cm high, is native to the northwest Himalay as, in northern India, West Pakistan, Tibet and China. In E. gerardiana total alkaloids vary from 0.8 to 1.4% of which 50% is ephedrine. Ephedra major Host (E. nebrodensis Tineo) grows wild in Afganistan, Pakistan and in the Mediterranean area of Spain, in Sicily, but also in the mountainous districts of Dalmatia (Biokovo and Mosor).