A study found that doctors commonly prescribe medications for off-label use, but almost never inform their patients of the fact. Using medications in this manner would not meet with approval from the U.S. Food and Drug Administration (FDA). All drugs that reach the market have gone through clinical trials in order to determine their efficacy and safety in their intended purpose. Once the FDA feels the medication has met all of its requirements, it then approves the label for the medication. The drug is then used for its intended purpose according to the label. The term "off-label" means using a medication to treat a problem that it was not originally intended for. It can also refer the use or form of a dosage of the drug that has not been approved by the FDA. A 2006 study found that one in five prescriptions were for off-label use.