Various herbal supplements are sold as weight loss aids. In many countries, including the United States, the authorities consider these products to be dietary supplements, not drugs. People can buy them without prescriptions, and the products are not subject to the same standards as drugs. In the United States, a drug company cannot sell a drug until it provides the U.S. Food and Drug Administration (FDA) with studies of its effectiveness and safety. The FDA approves a drug with potential dangerous side effects only after studies are done to show what these side effects might be. Doctors and patients can use this information to decide whether the risks of the drug are worth its potential benefits. Similar studies are not required before a company sells a dietary supplement, including herbal weight loss aids.