Cosmetic, Drug, or Both? The Test That Decides How a Product Is Regulated

In United States law, whether a product is a cosmetic or a drug is not decided by what is in the bottle. It is decided by what the product is claimed to do. The Federal Food, Drug, and Cosmetic Act draws a line: a cosmetic cleanses, beautifies, or alters appearance, while a product that claims to treat a disease or to affect the structure or any function of the body is a drug. The same cream, unchanged, can cross that line the moment the label promises something the law reads as a drug claim. That is why the test worth learning is not about ingredients at all. It is about intended use.

Two definitions, one deciding question

The FD&C Act defines a cosmetic as an article intended to be applied to the body "for cleansing, beautifying, promoting attractiveness, or altering the appearance." Moisturizers, perfumes, lipsticks, shampoos, and most skincare fall here. The definition of a drug is broader and stricter. A drug is an article intended for use in "the diagnosis, cure, mitigation, treatment, or prevention of disease," or an article "intended to affect the structure or any function of the body."

Read those two definitions side by side and the boundary appears. Beautifying and altering appearance sit on the cosmetic side. Treating disease or changing how the body is built or works sits on the drug side. The pivot word in both definitions is intended. Under FDA guidance, intended use can be established by claims on the label, in advertising, on a website, or in other promotional materials. A product marketed as though it were a cosmetic can still be regulated as a drug if its claims say it treats a condition or changes a bodily function.

The structure-or-function test

Here is the practical version of the test. Ask what the claim says the product does.

If the claim is about appearance, surface, or sensation, it reads as cosmetic. "Moisturizes the skin." "Adds shine." "Reduces the appearance of fine lines." Notice that last phrase carefully: the appearance of. That wording keeps the claim on the cosmetic side because it describes how skin looks, not what is happening beneath it.

If the claim asserts a change to the body's structure or function, or the treatment of a disease, it reads as a drug claim. "Regrows hair." "Stimulates collagen production." "Repairs the skin barrier." "Treats acne." "Reduces inflammation." Each of these asserts a physiological effect or a disease treatment, which is precisely the territory the drug definition covers.

A single product can carry both kinds of claims and therefore be both. The FDA's own example is an antidandruff shampoo: it is a cosmetic because it cleans the hair, and a drug because it treats dandruff. Fluoride toothpaste, sunscreen, and antiperspirants sit in the same dual category. Being both is not a loophole. It means the product must satisfy the requirements that apply to each classification.

Why the label of a category changes the evidence required

The reason this line matters to a reader is that the two categories carry very different evidence burdens. Cosmetics do not require FDA approval before they go to market. The manufacturer is responsible for safety, and the only cosmetic ingredients FDA reviews and approves in advance are color additives. A drug, by contrast, generally must be shown to be safe and effective for its intended use, either through the new drug approval process or by conforming to an applicable over-the-counter monograph. That is a far higher bar, built on human clinical evidence.

So when a product makes a drug-type claim while being sold as a cosmetic, one of two things is true. Either it has met the drug requirements, or it is making a claim it has not substantiated in the way the law contemplates. The claim, not the packaging, is what tells you which world the product is supposed to live in.

A separate agency, the Federal Trade Commission, governs advertising and asks a related question: is the claim substantiated? For health-related claims, the FTC standard is competent and reliable scientific evidence, which for most human health claims means well-conducted randomized human trials. Evidence from cell cultures, animal studies, single testimonials, or before-and-after anecdotes does not substantiate a human health claim on its own. When an endorsement is involved, any material connection between the endorser and the seller must be disclosed under the FTC endorsement rules.

"Cosmeceutical" is a marketing word, not a legal one

The term appears everywhere in beauty aisles, and it has no standing in the law. The FDA has stated plainly that the FD&C Act does not recognize any category called "cosmeceuticals." A product is a cosmetic, a drug, or both, and the word "cosmeceutical" does not change which of those it is. Industry uses it to signal that a cosmetic has drug-like benefits. But if a product truly affected the structure or function of the body, that effect would put it in the drug category with the evidence obligations that follow. The label "cosmeceutical" is best read as a claim of seriousness, not a grant of one.

One recent change belongs here. The 2022 Modernization of Cosmetics Regulation Act expanded FDA oversight of cosmetics, including facility registration and adverse event reporting. It did not move the cosmetic and drug line or turn "cosmeceutical" into a legal category.

How to read a label with this test in hand

Look for the verb. "Hydrates," "smooths," "conceals," and "reduces the appearance of" are cosmetic verbs. "Treats," "heals," "boosts," "stimulates," "repairs," and "restores function" point toward drug territory. Then check whether a product making a drug-type claim carries the marks of a drug: a Drug Facts panel, an active ingredient, and language tied to an approved use. A glossy structure-or-function promise on a product sold with no such backing is a signal to ask what evidence stands behind it. None of this is a verdict on whether a given product works or is worth buying. It is a way to see, at a glance, which set of rules the seller is inviting you to apply.

This article is educational and is not medical advice; for decisions about your own skin, health, or any specific product, talk with your own qualified clinician.