1.white odorless powdered or crystalline alkaloid from plants of the genus Ephedra (especially Ephedra sinica) or made synthetically; used to treat allergies and asthma.
2.A white, odorless, powdered or crystalline alkaloid, C10H15NO, isolated from shrubs of the genus Ephedra or made synthetically. It is used in the treatment of allergies and asthma.
