Ephedra plants are gymnosperm shrubs in the family Ephedraceae. Ephedra occur in dry climates over a wide area mainly in the Northern Hemisphere, across southern Europe, north Africa, southwest and central Asia and southwestern North America. Ephedra is also sometimes called sea grape (from the French raisin de mer), although that is also a common name for Coccoloba uvifera. Ephedra sinica is native to China. It is also known as "Chinese Ephedra", Ma Huang. Ma Huang is used to relieve acute muscular and rheumatic pains, as a stimulant, and in the cardio tonics in Ayurveda.