Which act requires drugs to be marked as safe and have adequate usage directions?

The Food, Drug, and Cosmetics Act is the legislation that mandates drugs to be proven safe for consumption and to provide adequate directions for use. This act was established to ensure that medications are not only effective but also safe for public use before they can be marketed. It requires that all pharmaceuticals undergo rigorous testing and demonstrate safety and efficacy, alongside labeling requirements that include clear dosage and usage information for consumers and healthcare providers.

By ensuring that drugs are properly labeled as safe with comprehensive usage instructions, the act aims to protect public health and provide consumers with the necessary information to use medications effectively and safely. This legislation highlights the government's role in regulating pharmaceutical products to prevent harm to individuals and promote informed use of medications.

The other options relate to different aspects of drug regulation. The Controlled Substances Act governs the classification and control of drugs that have potential for abuse, while the Drug Enforcement Administration Act pertains to the enforcement of these controlled substances. The Kefauver Harris Amendment primarily focuses on drug efficacy and the advertising of drugs, rather than safety and usage directions as mandated by the Food, Drug, and Cosmetics Act.