Ephedrin is a popular ingredient in herbal weight loss products. Ephedra is an herb used for centuries in China. In the United States, it has become a common ingredient in numerous dietary supplements.
Ephedra works by stimulating the central nervous system, much like adrenaline and caffeine.
Advocates say the herb can help people lose weight. Products containing ephedra also are marketed to athletes as energy boosters. Products containing the herb have become very popular and now include everything from capsules to powders to energy bars. Some of the most popular brands are made by the Metabolife company. Medical experts suggest that the stimulant can raise blood pressure and heart rate, cause vomiting, heart palpitations, dizziness, nervousness and more serious reactions, including heart attacks, seizures and strokes.