Zinc Pyrithione Shampoo From Korea: EU Ban, FDA Drug Rules

One Korean anti-dandruff shampoo can be three different products. In Seoul it is a cosmetic. In the US, the same bottle with the same promise is an over-the-counter drug. In the EU, it cannot go on the shelf at all.

The ingredient behind that split is zinc pyrithione, usually shortened to ZPT. It is one of the five dandruff actives named in the US rules. Korea also lists it among the actives for hair-loss-symptom shampoos, so it turns up in Korean scalp formulas that founders ask to private label.

When a founder sends me a scalp shampoo brief, my first question is not about foam or fragrance. It is where the bottle will be sold and what the front label will promise. Those two answers decide whether ZPT belongs in the formula.

What Is Zinc Pyrithione, and Why Do Korean Scalp Lines Use It?

Zinc pyrithione is a zinc complex of pyrithione that slows the growth of Malassezia, the scalp yeast linked to dandruff. Lab work in Antimicrobial Agents and Chemotherapy showed how. ZPT raises copper levels inside fungal cells and disables iron-sulfur proteins the yeast needs to grow, an effect also seen in Malassezia globosa (Reeder et al., 2011).

ZPT does not dissolve in a shampoo. It sits in the formula as fine particles. A review in the Journal of Drugs in Dermatology calls those particles a depot. Some stay on the scalp after rinsing and keep releasing active molecules (Schwartz, 2016). That is why suspension, spreading, and deposition decide whether a ZPT shampoo works in the shower.

Korean rules allow ZPT in both anti-dandruff shampoos and the hair-loss-symptom shampoos that Korea classes as functional cosmetics (KCIA). So a Korean stock scalp formula can contain it even when your brief never asked for a dandruff product. Read the full ingredient list before you sample.

One Ingredient, Three Different Legal Answers

ZPT is a restricted cosmetic ingredient in Korea, a monograph drug active in the US, and a prohibited substance in the EU. Here is what that means for a single rinse-off shampoo.

Note the overlap. A Korean dandruff shampoo at Korea's 1.0 percent cap already sits inside the US rinse-off range. The active level can cross the Pacific unchanged. The paperwork, the factory status, and the label cannot.

Why Does a Dandruff Claim Turn a Shampoo Into a Drug in the US?

US law sorts products by intended use, and FDA uses the antidandruff shampoo as its own example of a product that is both a cosmetic and a drug. It cleanses hair, which is cosmetic, and it treats dandruff, which is a drug use, so it must meet both sets of rules (FDA).

The drug side follows an OTC monograph. An OTC monograph is a federal rule that lists the actives, strengths, and label wording a nonprescription drug category must follow. The dandruff monograph names five actives: coal tar, pyrithione zinc, salicylic acid, selenium sulfide, and sulfur, each within a set range (21 CFR 358.710).

It also fixes the words. The label identifies the product as a "dandruff shampoo" or "antidandruff shampoo." Indications follow set phrases such as "controls the symptoms of dandruff" or "helps prevent recurrence of scalp flaking and itching associated with dandruff." Warnings include "For external use only," and shampoo directions say to use at least twice a week (21 CFR 358.750).

Dropping the word "dandruff" is not a clean workaround. FDA reads intended use from claims, from consumer perception, and from ingredients with a well-known therapeutic use; its example is fluoride in toothpaste (FDA). A shampoo built around a known dandruff active, sold to shoppers searching for dandruff help, raises the same question.

The OTC path then adds drug-side duties: a drug-registered factory, drug listing, a Drug Facts label, and drug manufacturing rules. The salicylic acid OTC guide for Korean acne products walks through that sequence step by step, and it applies to a dandruff shampoo too.

Hair-Loss Claims Hit a Harder Wall

A US label that promises to prevent hair loss or grow hair needs an approved new drug application. No OTC monograph covers hair growers, and the rule names biotin, other B vitamins, and dexpanthenol among ingredients without adequate data for those uses (21 CFR 310.527).

That matters because Korea runs a different system. Products that help relieve hair-loss symptoms moved from quasi-drugs into Korea's functional cosmetic category in 2017. The notified actives for them include dexpanthenol, biotin, and ZPT (Kyunghyang Shinmun). Even in Korea the claim stops at relieving hair-loss symptoms; "prevents hair loss" and hair-growth wording are off-limits there too. A Korean hair-loss shampoo can carry its symptom claim legally at home and still be an unapproved new drug in the US.

FDA lists "restore hair growth" as a claim that makes a product a drug (FDA). Unapproved new drugs promoted in the US can be detained at import without physical examination (Import Alert 66-41).

Appearance and feel claims keep a shampoo on the cosmetic side: thicker-looking hair, a softer feel, a scalp that feels clean and refreshed. Translate the Korean copy before the label goes to print, not after.

What Changes If You Also Sell in the EU?

A ZPT shampoo cannot be sold as a cosmetic in the EU. Annex II is the EU list of substances prohibited in cosmetic products. Regulation (EU) 2021/1902 added zinc pyrithione to it from March 1, 2022, after ZPT was classified as toxic for reproduction (EUR-Lex).

EU anti-dandruff formulas now lean on other actives. Climbazole remains permitted under limits the EU tightened in 2019 (Regulation (EU) 2019/698), and ingredient suppliers market piroctone olamine as a ZPT replacement (Personal Care Insights).

Here is the trap. Neither climbazole nor piroctone olamine is on the US dandruff monograph list, so neither can anchor a monograph dandruff claim in the US (21 CFR 358.710). An EU-safe formula and a US dandruff drug are two different products.

Selling in Europe also means an EU Responsible Person and a CPNP notification before launch. The EU CPNP registration guide for Korean cosmetics covers that side.

Five Formula Points to Settle With Your Korean ODM

A ZPT shampoo succeeds or fails on particle handling. The active has to stay evenly suspended, spread over the scalp, and remain chemically active through shelf life (Schwartz, 2016). Put these five points in writing before sampling.

1. Raw material grade. Ask for the ZPT supplier, the grade, and its certificate of analysis.
2. Suspension over shelf life. Ask how the base keeps particles from settling, and see stability data at your agreed conditions.
3. Batch assay. A US drug batch must be tested for the identity and strength of each active before release (21 CFR 211.165). Ask which method the lab uses for ZPT.
4. Metal contact. Pyrithione moves metal ions readily, which is part of how it works (Reeder et al., 2011). Ask how the formula and packaging limit trace metal contact.
5. Drug-side status. Ask whether the plant is registered with FDA as a drug establishment and has shipped OTC monograph products to the US before.

Which Path Fits Your Scalp Launch?

Pick the path from your markets and your hero claim. If dandruff relief is the reason the product exists and the US is the main market, the OTC route with ZPT fits. If the brand also sells in the EU, or the story is scalp care rather than dandruff, a cosmetic formula without ZPT is simpler.

• US only, dandruff is the hero claim. OTC shampoo with ZPT in the rinse-off range, a drug-registered factory, and Drug Facts.
• US and EU, dandruff claim needed in the US. Two formulas: a ZPT drug for the US and an EU cosmetic built on a permitted active.
• Scalp-care story, no disease claims. Cosmetic formula, appearance claims, and MoCRA registration and listing. The Korean scalp care private label guide covers formats and positioning.
• Hair-growth story. Treat it as a drug development project, not a private label launch.

Whichever path you choose, confirm the US import basics early. The FDA import guide for Korean skincare covers registration, listing, and labeling for the cosmetic side, and the step-by-step guide to starting a K-beauty brand covers factory selection.

Frequently Asked Questions

Is zinc pyrithione banned in Korea?
No. Korea allows ZPT up to 1.0 percent in rinse-off dandruff and itch shampoos and conditioners and in hair-loss-symptom cosmetics, and up to 0.5 percent as a preservative in rinse-off products. Other product types cannot use it (KCIA).

Can a Korean ZPT shampoo be sold in the US as a cosmetic if the label never says dandruff?
Only with tight discipline. FDA reads intended use from claims, consumer perception, and ingredients with a well-known therapeutic use (FDA). Your listing copy, ads, and search keywords all have to stay clear of dandruff.

Does Korea's hair-loss functional cosmetic status help with a US launch?
No. The US has no OTC monograph for hair growth or hair loss prevention, so those claims require an approved new drug application (21 CFR 310.527). Rewrite the copy into appearance language for the US.

Is piroctone olamine an approved dandruff active in the US?
No. The US dandruff monograph lists coal tar, pyrithione zinc, salicylic acid, selenium sulfide, and sulfur (21 CFR 358.710). A piroctone olamine shampoo cannot make a monograph dandruff claim.

By Liz Song, K-beauty sourcing consultant.