Zinc Pyrithione

Cosmetic preservative that is effective against many pathogens

Most popular in anti-dandruff shampoos

May be suitable for “fungal acne”

Comes in the form of white to slightly yellow crystals as a raw material

Zinc pyrithione is a cosmetic preservative and anti-fungal ingredient that is effective against many pathogens. It’s been in use for over 50 years and is most popular as an active ingredient in over-the-counter anti-dandruff shampoos. It’s also found in body washes, facial cleansers, treatment creams, and other personal care products. It is approved by the United States Food & Drug Administration for use in leave-on products in amounts between 0.1–0.25% and from 0.3–2% when formulated for use in rinse-off products. These amounts are considered safe for skin.

Zinc pyrithione’s mechanism of action still isn’t completely understood; researchers just know it works for a wide range of concerns related to overgrowths of various strains of yeast and other fungi. It seems to have a disruptive effect on these substances, dismantling them so they can no longer replicate and cause further problems for skin and scalp. Interestingly zinc pyrithione tends to work differently depending on what it’s up against, one of the reasons it works for such a broad range of yeast-related issues.

In recent years, zinc pyrithione has gained attention in social media circles as a key ingredient to treat “fungal acne” (also known as Malassezia folliculitis). While there are studies supporting this assertion, diagnosis and treatment of this condition should be handled by dermatologist.

As a raw material, zinc pyrithione comes in the form of white to slightly yellow crystals. Technically speaking, this is an aromatic zinc compound, which is a chemistry term to describe an ingredient whose molecular structure has a specific ring structure referred to as “aromatic”. This is not to be confused with “aromatic” as in perfume or fragrance ingredients.

See: Zinc