Are period underwear FDA-regulated? Why there is no ingredient list

One rulebook, three device classes

The FDA says all menstrual products sold in the United States are regulated as medical devices, and its consumer page on menstrual products files period underwear under menstrual pads. That sounds like more oversight than it is. In the FDA's device rules, an unscented menstrual pad is a Class I device, the lowest class: it must follow general controls (rules on manufacturing, labeling, and reporting malfunctions and adverse events) and it is exempt from premarket notification, so a pad, or a pair of period underwear, can go on sale without the FDA reviewing it first. A menstrual cup is Class II with special controls, also exempt from premarket notification. An unscented tampon is Class II with performance standards, and tampons are the example the FDA gives of a product it reviews before it reaches the market.

And here is the part that surprises people: none of the three classes requires an ingredient list. Being a regulated device controls how a product may be made, labeled and sold; it does not force disclosure of what it is made of. One more line worth knowing, read from the regulation's own text: the Class I pad category excludes pads with added antimicrobial agents. The FDA's consumer page does not say how silver-treated period underwear is classified, and neither do we; the silver guide covers what the silver is there for.

Why the gap matters

No ingredient-disclosure requirement means a shopper cannot look at the label and see whether PFAS or silver were used. That vacuum is exactly what independent lab testing and the class-action lawsuits stepped into - they became the disclosure mechanism the label was not providing. It is also why a brand that voluntarily publishes third-party testing is doing something meaningful: it is opting into transparency the law does not require of it.

What is changing: state laws

States are closing the gap. New York passed the first menstrual-product ingredient-disclosure law in 2021, requiring intentionally added ingredients to be listed. New York has since gone further with a law banning PFAS and other toxic chemicals in period products, taking effect in December 2026, joining a group of states (around eight) that ban PFAS in period products. California's T.A.M.P.O.N. Act bans intentionally added PFAS in menstrual products, including period underwear. So the disclosure-and-safety floor is rising, state by state, even though the federal rules have not changed.

Sources

The regulatory facts above trace to:

• All menstrual products are regulated as medical devices, period underwear is filed under menstrual pads, and tampons are the FDA's example of a product reviewed before sale: FDA, "Menstrual Product Options: Facts and Safe Use." Read 2026-09-05.
• Unscented menstrual pad, Class I (general controls), exempt from premarket notification, excluding pads with added antimicrobial agents: 21 CFR 884.5435. Menstrual cup, Class II (special controls), exempt from premarket notification: 21 CFR 884.5400. Unscented menstrual tampon, Class II (performance standards): 21 CFR 884.5470. All via govinfo.gov, 2023 edition. Read 2026-09-05.
• No class requires an ingredient list: the FDA page describes the rules as manufacturing, labeling and adverse-event reporting, and none of the three regulations above mentions ingredient disclosure.
• New York 2021 ingredient-disclosure law, and New York PFAS-in-period-products ban effective December 2026: NRDC.
• California T.A.M.P.O.N. Act (bans intentionally added PFAS in menstrual products including period underwear): Bloomberg Law.