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Common Name(s): Octopirox,piroctone ethanolamine,om-90
CAS Number: 68890-66-4
DESCRIPTION
What It Does: Provides iron chelation anti-malassezia anti-dandruff with lower environmental impact than zpt.
Why It's Used: Environmentally-preferable anti-dandruff โ piroctone olamine's lower aquatic toxicity vs zinc pyrithione provides comparable anti-dandruff efficacy with improved environmental profile for rinse-off scalp products.
How It Works: Hydroxamic acid chelates iron from malassezia โ iron-depleted malassezia cannot produce the lipases initiating the dandruff cascade. also directly antimicrobial at higher concentrations. unique iron-starvation mechanism vs zpt membrane disruption or climbazole cyp51 inhibition.
Typically Found In: Anti-dandruff shampoos,scalp treatments (eu preferred)
TECHNICAL DETAILS
Primary Category: Active ingredient โ cosmetic active
Secondary Functions: Skin conditioning
Application Areas:
Facial Skincare
Body Care
Hair Care
Beard Care
Color Cosmetics (Makeup)
Dietary/Oral Supplements
Typical Concentration Range: 0.5%โ1%
SOURCING & ETHICS
Vegan Status: Conditional - supplier confirmation required
Halal Status: Unverified - supplier confirmation required
Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier. [audit 2026-07-29 rev2: the record's own source_notes does not assert a non-animal origin, or instructs the reader to verify with the supplier; "yes" asserts knowledge the record does not hold. determination requires shariah-panel sign-off.]
SKIN COMPATIBILITY
Irritancy Rating: 1/5 โ very low
Comedogenicity Rating: 0/5 โ non-comedogenic
Sensitivity Concerns: Well-tolerated by most skin types.
Safe for Sensitive Skin: Yes
SAFETY & COMPATIBILITY
Safety Profile: Eu cosmetic approved. not fda otc approved for dandruff claims in us.
Works Well With: Standard skincare actives
Avoid Combining With: No known significant incompatibilities
SCIENTIFIC NOTE
Piroctone olamine's unique iron-starvation antifungal mechanism (starving malassezia of essential iron) provides anti-dandruff from nutrient deprivation rather than direct cell killing โ a fungistatic rather than fungicidal approach with different ecological implications for scalp microbiome impact vs bactericidal/fungicidal mechanisms.
Last Verified: 2026-03-12
Primary Sources: Cosing database,boyle et al. piroctone olamine anti-dandruff study