Phenylpropanolamine is a chemical compound often used as a decongestant and appetite suppressant. It works by narrowing blood vessels to reduce swelling and congestion in the nasal passages. Additionally, it can help decrease appetite, making it a common ingredient in weight loss products. However, Phenylpropanolamine has been associated with serious side effects, including an increased risk of stroke. Due to these safety concerns, the U.S. Food and Drug Administration (FDA) advised against its use in over-the-counter medications in 2000. As a result, many products containing this compound have been removed from the market.