ZINC PYRITHIONE - Skin Care Ingredients Curated By Mia Seilern

By KimReviewed Nataly

⚠️ Data is provided for informational purposes only. It may contain inaccuracies and should be independently verified. This is not medical advice. Consult a healthcare professional before making health decisions.

Description: ZINC PYRITHIONE — antimicrobial agent (mainly anti-dandruff use, also functions as preservative).

All Functions: antimicrobial agent (mainly anti-dandruff use, also functions as preservative)

Quick Facts:

Category: preservative
Regulatory Note: Prohibited in the EU

Proven Benefits At A Glance:

Zinc pyrithione is an antifungal ingredient used for over 50 years, most commonly in dandruff and seborrheic dermatitis shampoos
It works against Malassezia yeast, the primary microorganism involved in dandruff and seborrheic dermatitis
The ingredient has a broad antimicrobial spectrum, affecting fungi, gram-positive and gram-negative bacteria
It’s delivered as tiny particles that stick to the scalp and slowly release active material for extended effects
Research shows it can also be used as a preservative in alcohol-based skin antisepsis products

Safety: AvoidResearch confidence: Good

Safety tier is a starting heuristic from regulatory status and comedogenic rating, not a dermatological verdict — see our Terms for the full disclaimer. Research confidence reflects how many real cited studies back this ingredient, not the strength of their findings.

🧪 ZINC PYRITHIONE

ZINC PYRITHIONE

CAS Number: 13463-41-7

Also Known As: —

Category: preservative

EC Number: 236-671-3

Korean Name: 징크피리치온

Pyridine-2-thiol-1-oxide, zinc complex (2:1)

ZINC PYRITHIONE is a preservative ingredient used in skincare formulations.

antimicrobial agent (mainly anti-dandruff usealso functions as preservative)

🌍 Regulatory Status

EU: ProhibitedUS: No restriction on file

📊 Comedogenicity

No data yet

Not rated for this ingredient yet.

📚 Research & Evidence

PUBMED CITATIONS

Data sources: EU CosIng PubMed

🔬 The Science

Zinc pyrithione (ZnPT) is a rationally designed molecule modeled after aspergillic acid, a naturally occurring antimicrobial compound (J Drugs Dermatol, 2016). Here’s how it works: #1: It targets dandruff and seborrheic dermatitis, which are driven by microbial imbalance involving Malassezia yeast species (Int J Mol Sci, 2021). The ingredient shows anti-fungal activity with minimum inhibitory concentrations of 10-15 ppm against the most common scalp yeasts—Malassezia globosa and Malassezia restricta (Int J Mol Sci, 2021). In human studies, zinc pyrithione treatment decreased M. restricta on the scalp, validating its antifungal efficacy (Med Mycol, 2021). #2: Its effectiveness comes from two key attributes: broad antimicrobial spectrum (affecting fungi and bacteria) and very low solubility, which means it’s formulated as particles rather than dissolved molecules (J Drugs Dermatol, 2016).

These particles deposit and remain on skin surfaces—even in rinse-off products like shampoos—and act as slow-release reservoirs, gradually releasing active molecules to control microbial populations and provide sustained benefits (J Drugs Dermatol, 2016). #3: For this particle-based delivery to work optimally, the formulation must achieve uniform distribution across the scalp surface and into hair follicles, maintain physical stability, and keep the zinc pyrithione chemically active (J Drugs Dermatol, 2016). This explains why products with identical zinc pyrithione concentrations can perform differently. #4: Beyond scalp use, zinc pyrithione functions as a preservative in alcohol-based skin antisepsis products, extending antimicrobial effects beyond what alcohol alone provides (Am J Infect Control, 2005).

According to that source, zinc pyrithione-preserved alcohol formulations can exceed the antimicrobial efficacy of iodine and chlorhexidine gluconate. Research has also demonstrated methods to visualize and measure zinc pyrithione distribution on the scalp using advanced imaging techniques (Photochem Photobiol, 2019), supporting ongoing investigation into formulation optimization.