Enforcement of the new law came swiftly. Within two months of the passage of the act, the FDA began to identify drugs such as the sulfas that simply could not be labeled for safe use directly by the patient--they would require a prescription from a physician. The ensuing debate by the FDA, industry, and health practitioners over what constituted a prescription and an over-the-counter drug was resolved in the Durham-Humphrey Amendment of 1951. From the 1940s to the 1960s, the abuse of amphetamines and barbiturates required more regulatory effort by FDA than all other drug problems combined. Furthermore, the new law ushered in a flood of new drugs applications, over 6,000 in the first nine years, and 13,000 by 1962.
Illegal sales of amphetamines and barbiturates occupied more regulatory concern at FDA than all other drug problems combined from the 1940s to the 1960s. Interdiction in some venues required undercover tactics, as indicated here by these two inspectors posing as truck drivers.
A new drug law in that year, the Kefauver-Harris Amendments, derived in large part from hearings held by Senator Estes Kefauver. As with the 1938 act, a therapeutic disaster compelled passage of the new law; in this case the disaster was narrowly averted. Thalidomide, a sedative that was never approved in this country, produced thousands of grossly deformed newborns outside of the United States. The new law mandated efficacy as well as safety before a drug could be marketed, required FDA to assess the efficacy of all drugs introduced since 1938, instituted stricter agency control over drug trials (including a requirement that patients involved must give their informed consent), transferred from the Federal Trade Commission to the FDA regulation of prescription drug advertising, established good manufacturing practices by the drug industry, and granted the FDA greater powers to access company production and control records to verify those practices. Three years later Congress gave the FDA enhanced control over amphetamines, barbiturates, hallucinogens, and other drugs of considerable abuse potential in the Drug Abuse Control Amendments of 1965. That function was consolidated with similar responsibilities in 1968 under an organization that gave rise to the Drug Enforcement Administration.
The first food standards to be issued under the 1938 act were for canned tomato products; by the 1960s about half of the food supply was subject to a standard. As food technology changed and the number of possible ingredients--including fortifying nutrients--grew, the agency developed recipe standards for foods, lists of ingredients that could lawfully be included in a product. A food that varied from the recipe would have to be labeled an imitation.
Following hearings in the early 1950s under Representative James Delaney, a series of laws addressing pesticide residues (1954), food additives (1958), and color additives (1960) gave the FDA much tighter control over the growing list of chemicals entering the food supply, putting the onus on manufacturers to establish their safety. While tolerances could be established for many chemicals, a provision of the 1958 law, the Delaney Clause, banned any carcinogenic additive.
FDA pursued numerous cases of food misbranding in the 1950s and 1960s, most deriving from false nutritional claims and unscientific enrichment, with mixed success in the courts. In 1973, following hearings the agency convened to address the vitamin fortification of foods and the claims made for dietary supplements, the FDA issued regulations for special dietary foods, including vitamins and minerals. The public response to these regulations helped lead Congress in 1976 to prohibit the FDA from controlling the potency of dietary supplements, although the agency maintained authority to regulate enriched foods.