The vast majority of enforcement of consumer health protection standards is handled by the U.S. Food and Drug Administration ("FDA"), although certain cases may be referred to law enforcement officials, as well, for potential criminal prosecutions in extreme circumstances involving widespread injury and conduct that rises to the level of a criminal act. The FDA is responsible for reviewing and approving every medication that is offered for sale in U.S. markets, including both prescription and non-prescription drugs. Nonetheless, even full compliance with FDA standards is not a defense for a drug manufacturer when a consumer has been harmed or injured from taking a certain drug. For instance, a drug company has a duty to warn a consumer of potential side effects from taking the drug, no matter how serious. In some circumstances, there are certain warning labels and information leaflets that manufacturers must provide to consumers along with the drug.