Drugs work in your body in a variety of ways. They can interfere with microorganisms (germs) that invade your body, destroy abnormal cells that cause cancer, replace deficient substances (such as hormones or vitamins), or change the way that cells work in your body. There are more than 8,000 medications available either by prescription or over-the-counter. Some can be used to treat several different health conditions. Aspirin, for example, can be used to treat pain, inflammation, and fever. In addition, aspirin can prevent heart attacks if taken on a regular basis.
