Medicines can treat diseases and improve your health. If you are like most people, you need to take medicine at some point in your life. You may need to take medicine every day, or you may only need to take medicine once in a while. Either way, you want to make sure that your medicines are safe, and that they will help you get better. In the United States, the Food and Drug Administration is in charge of ensuring that your prescription and medicines are safe and effective.