## Facts

- Bacto-Unidisk consisted of antibiotic-impregnated discs used in clinical laboratories as a screening test to determine which antibiotics are effective against particular bacteria.
- Laboratory personnel placed the discs on bacterial culture plates to assess susceptibility, and physicians used the results to choose antibiotic therapy for patients.
- Under the Federal Food, Drug, and Cosmetic Act (FDCA), a “drug” includes “articles intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease.”
- The FDA treated antibiotic sensitivity discs as antibiotic “drugs” subject to premarket batch certification regulations issued under the FDCA’s antibiotic provisions.
- The manufacturer marketed Bacto-Unidisk without complying with batch certification requirements.
- The United States seized and sought condemnation of the discs under the FDCA’s seizure provision, proceeding on the theory that the discs were regulated drugs.

## Issues

1. Whether an antibiotic sensitivity disc used in laboratory testing to guide antibiotic therapy is a “drug” as an “article[] intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease” under the FDCA.
2. Whether the discs should instead be treated only as “devices,” placing them outside the FDCA’s antibiotic batch certification scheme and limiting available enforcement tools.

## Decision

- The Supreme Court reversed the Sixth Circuit.
- The Court held that antibiotic sensitivity discs are “drugs” within the FDCA’s definition because their intended use is to aid diagnosis and treatment by guiding antibiotic selection.
- The Court upheld FDA authority to require premarket batch certification for such discs under the antibiotic provisions.
- Because the discs were distributed without required certification, seizure and condemnation were authorized.

## Legal Principles

- The FDCA is construed liberally to carry out its public-health purpose; coverage is not limited by narrowly technical readings of statutory definitions.
- “Intended use” is the primary statutory criterion for determining whether an article is a “drug” under the FDCA’s disease-related definition.
- An article can qualify as a “drug” even if it has no direct pharmacological effect on the body and is used indirectly (e.g., in a laboratory) to guide diagnosis or treatment.
- The statutory categories are not necessarily mutually exclusive; an item that resembles a “device” in ordinary usage may still be regulated as a “drug” if its intended use fits the drug definition.
- Products affecting the safety and effectiveness of drug therapy may fall within FDA drug authority when inaccurate or substandard performance could lead to ineffective or dangerous treatment choices.

## Conclusion

The Court treated antibiotic sensitivity discs as “drugs” under the FDCA because they are intended to be used to diagnose and treat disease by guiding antibiotic therapy, validating FDA premarket batch certification requirements and permitting seizure of uncertified products.


United States v. An Article of Drug . . . Bacto-Unidisk, 394 U.S. 784 (1969)