FDA issues a nationwide recall of all over-the-counter dietary supplements containing 100 milligrams or more of L-Tryptophan, due to a clear link between the consumption of L-tryptophan tablets and its association with a U.S. outbreak of Eosinophilia Myalgia Syndrome (EMS), characterized by fatigue, shortness of breath, and other symptoms. By 1990 the Centers for Disease Control and Prevention confirm over 1,500 cases of EMS, including 38 deaths, and FDA prohibits the importation of l-tryptophan.

Responding to increasing illicit traffic, Congress passes the Anabolic Steroid Act of 1990, which identifies anabolic steroids as a class of drugs and specifies over two dozen items as controlled substances. In addition, a four-part definition of this class is established to permit new, black market compounds to be assigned to this category, and thus subject to regulation as controlled substances.

Nutrition Labeling and Education Act requires all packaged foods to bear nutrition labeling and all health claims for foods to be consistent with terms defined by the Secretary of Health and Human Services. The law preempts state requirements about food standards, nutrition labeling, and health claims and, for the first time, authorizes some health claims for foods. The food ingredient panel, serving sizes, and terms such as "low fat" and "light" are standardized.

Safe Medical Devices Act is passed, requiring nursing homes, hospitals, and other facilities that use medical devices to report to FDA incidents that suggest that a medical device probably caused or contributed to the death, serious illness, or serious injury of a patient. Manufacturers are required to conduct post-market surveillance on permanently implanted devices whose failure might cause serious harm or death, and to establish methods for tracing and locating patients depending on such devices. The act authorizes FDA to order device product recalls and other actions.