Ephedrine is a common ingredient in herbal supplements used for weight loss. Ephedrine is used in asthma medicine, as well as to make methamphetamine, more commonly known as speed. In fact, there's only a slight difference chemically between methamphetamine and ephedrine. Ephedrine can slightly suppress your appetite, but few studies have shown it to be independently effective in weight loss.Ephedrine can also be dangerous. It can cause high blood pressure, irregular heartbeat, insomnia, nervousness, tremors, seizures, heart attacks, strokes and even death. Ephedrine can also interact with many prescription and over-the-counter medications.