Ephedrine is a sympathomimetic amine commonly used as a decongestant. Chemically speaking, it is an alkaloid derived from various plants in the genus Ephedra (family of the Ephedraceae). Its salt, ephedrine hydrochloride has various uses against its sympathomimetic effect.
Ephedrine has an optical isomerism and has two centers of chirality. By convention the enantiomers which have a stereochemistry opposite around the centers of chirality are designated as ephedrine, while pseudoephedrine has same stereochemistry around the chiral carbon. That is, the enantiomers (1R, 2R) and (1s, 2S) are called pseudoephedrine, so that the (1R, 2S) enantiomers and (1s, 2R) are called ephedrine.
