Page 43 - Biomedical Engineering and Design Handbook Volume 2, Applications

22 MEDICAL DEVICE DESIGN

Any device that diagnoses, cures, mitigates, treats, or prevents disease in a human or animal is
included.

(h) The term “device” (except when used in paragraph (n) of this section and in sections 331 (i), 343 (f),
352 (c), and 362 (c) of this title) means an instrument, apparatus, implement, machine, contrivance,
implant, in vitro reagent, or other similar or related article, including any component, part, or accessory,
which is—
(1) recognized in the official National Formulary, or the United States Pharmacopeia, or any supplement
to them,
(2) intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, treatment,
or prevention of disease, in man or other animals, or
(3) intended to affect the structure or any function of the body of man or other animals, and

which does not achieve its primary intended purposes through chemical action within or on the body of
man or other animals and which is not dependent upon being metabolized for the achievement of its pri-
mary intended purposes.
21 U.S.C. § 321(h)

In contrast, drugs are defined in wording almost identical to devices, except that drugs achieve
their effectiveness by chemical interaction with the body or by being metabolized. Usually devices
act by mechanical, electrical, magnetic, or some other physical interaction with the body. Sometimes
this boundary between drugs and devices is not clear.
It is further complicated by the boundary between drugs and cosmetics. Cosmetics are articles
intended to be rubbed, poured, sprinkled, or sprayed on, introduced into, or otherwise applied to the
human body for cleansing, beautifying, promoting attractiveness, or altering the appearance. ∗
How does this affect your morning toothbrushing? When you brush your teeth you are using a
medical device—the brush. The brush works in a mechanical manner on your teeth to remove
unwanted material. The toothpaste you use could be a cosmetic in that it is applied to the teeth to
cleanse. However, if you choose a fluoride toothpaste you are using a drug, since the fluoride is
metabolized by the body in order to prevent tooth decay. If you choose to use an oral rinse to reduce
adhesion of plaque to your teeth before you brush, you are using a medical device. The oral rinse
loosens plaque that is then removed by your brushing.
Do not assume that the form of the product, liquid versus mechanical, determines whether it is a
device. You must look through the sometimes arcane rules and consider its interaction with other
products to determine the nature of any object designed to affect the human body.
The single most important determinant of the legal status of any item is what it is intended to
be. As is discussed below, “claims” as to what a product is or does determine its legal category.
A device can be a nonmedical consumer product or a medical device, depending on how you
label it.

2.3 WHAT IS FDA?

While medical devices and other medical products are regulated by many government agencies, the
U.S. Food and Drug Administration (FDA) is the primary regulator.

∗ 21 U.S.C. § 321(i).