What defines a “medical device” under federal law?

A "medical device" under federal law is specifically characterized as an instrument, machine, or implant designed for medical use that can influence the body's structure or functions without being metabolized. This definition is rooted in the Federal Food, Drug, and Cosmetic Act, which categorizes devices based on their intended purpose and how they interact with the body.

In this context, the term "medical use" underscores that a device is intended for diagnosing, treating, or preventing diseases and conditions. The stipulation that a medical device should not be metabolized highlights that it is not a drug or a biological product; instead, it functions mechanically or physically to achieve a medical effect.

For instance, a pacemaker or an MRI machine are examples of devices that fulfill this definition well—they affect physiological functions or enable medical diagnostics without being chemically altered within the body.

In contrast, other options do not fit the federal definition of a medical device. Recreational items, aesthetic only implants, and products that only measure health metrics do not meet the criteria for influencing structures or functions for medical purposes in the same way. This clear distinction helps to ensure that medical devices are appropriately regulated for safety and efficacy before they can be marketed and used in healthcare settings.