The scientific names for ephedra are Ephedra sinica and Ephedra gerardiana. Common names are ephedra, ma-huang, and desert herb. They are not subject to the same scrutiny and regulations as prescription medicines. The active ingredient in ephedra that is used in medicines is called ephedrine. The amount of ephedrine in each plant can vary so much that the same dosage of ephedra can produce very different effects.
Ephedrine is a stimulant of the central nervous system.
There is no scientific evidence that ephedra helps you lose weight. It can be dangerous if taken for that purpose. Ephedra is taken as a tablet, capsule, or liquid. It can also be prepared as a tea to drink. Follow the directions printed on the product label or given by your doctor.