Under the FDCA, what does the term "drug" encompass?

The term "drug" under the Federal Food, Drug, and Cosmetic Act (FDCA) is defined to include substances intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in humans or animals. This broad definition encompasses not only prescription medications but also over-the-counter drugs that serve specific medical purposes.

By focusing on substances for disease diagnosis and treatment, the correct answer highlights the primary role that these products play in healthcare. This definition is fundamental for understanding the regulatory framework surrounding pharmaceuticals, including the approval, marketing, and use of drugs. Other options do not fall under this specific classification of "drug" as defined by the FDCA. For example, food products intended for human consumption are generally regulated differently and do not have the same implications as drugs. Similarly, while substances used for cosmetic purposes and non-prescription health supplements are regulated, they do not meet the criteria that classify them as drugs under the FDCA. Understanding this distinction is crucial for anyone involved in pharmacy practice or regulatory affairs.