Ma-Huang, an evergreen shrub native to Northern China, is one species of Ephedra. It’s been called the world’s oldest medicine, as it has been used in traditional Chinese medicine for over 5000 years.  Medicinal uses have ranged from treating colds, asthma and hay fever to various kidney ailments. Several amphetamine-like alkaloids can be extracted from Ephedra, including the strongly bioactive molecules ephedrine and pseudoephedrine, which are remarkably similar to each other, differing only in the three dimensional arrangement in space of atoms attached to two carbon centres.

One Ephedra extract, which can also be made synthetically, is pseudoephedrine, which has fewer central stimulant effects than ephedrine.  Pseudoephedrine is used in many pharmaceutical decongestants and antiasthmatic medicines as a nasal decongestant and a bronchodilator to relax and open air passages to the lung to increase the flow of air.