Zinc Pyrithione Shampoo

What is Pyrithione Zinc?

Zinc pyrithione is a coordination complex of zinc compound and 1-hydroxy-2(1H)-pyridinethione, which is commonly known as pyrithione. According to the American Chemical Society (ACS), it was first officially synthesized by E. Shaw and his colleagues in 1950.

However, the zinc derivative was patented by Olin Mathieson in 1956, and ever since it has been used due to its antifungal and antibacterial properties. It works by inhibiting the growth of fungal and bacterial cells on the skin, making it an effective treatment option for seborrheic dermatitis and dandruff.

Seborrheic Dermatitis and Pyrithione Zinc 

Seborrheic dermatitis is often known as a more severe form of dandruff. It is a common skin condition that is believed to be caused by a combination of factors, such as the production of excess sebum on the skin and the overgrowth of Malassezia yeast, a type of fungus that is naturally present on the skin. 

Now, the question arises: How can zinc pyrithione help with seborrheic dermatitis and dandruff? Most researchers believe that its effectiveness comes from two key factors:

• Antimicrobial Activity: It works against various microbes and controls their growth, including Malassezia globosa, the culprit for seborrheic dermatitis and dandruff. 

• Low Solubility: Due to its low solubility, the fine particles of zinc pyrithione stay on the skin even after washing. These particles help provide long-lasting protection against fungi and bacteria. 

This is why it is often added to anti-dandruff and anti-seborrheic dermatitis shampoo. 

Effectiveness of Pyrithione Zinc Shampoo

Zinc Pyrithione, also known as ZPT, when used at the appropriate percentage, with the appropriate Drug Facts label, and made at a factory that follows current Good Manufacturing Practice, is an FDA-approved active ingredient proven to be highly effective in helping reduce scalp flakes associated with seborrheic dermatitis and dandruff.

This ingredient has been shown in many double-blind studies to be effective in controlling the clinically evident scaling in dandruff. Three different types of zinc pyrithione shampoo were evaluated in 13 clinical trials conducted by 5 investigators at different test sites. All tests were double-blinded. One group used a control shampoo and the other, the zinc pyrithione shampoo. 

The study participants shampooed once or twice a week for 6-10 weeks. Results showed that all three medicated shampoos were effective in reducing dandruff. The use of shampoo base alone (the control) showed some improvement in scalp scaling in the above studies. Thus, frequent shampooing has been suggested as a treatment for dandruff [1].

A Study from the International Journal of Cosmetic Science in 2014 used spectroscopic technology to look at the topmost layer of skin, the stratum corneum, to compare a dandruff scalp to a non-dandruff one and see the effects of a zinc pyrithione shampoo. 

It showed that the dandruff scalp has lower natural moisturizing factors, elevated levels of urea, lower levels of lactic acid, and deeper sebum than the dandruff-free scalp. 

The pyrithione zinc shampoo helped restore those levels to the characteristics of a normal or dandruff-free scalp [2].

Happy Cappy and Zinc Pyrithione

Cradle cap or infant dandruff is a flaky, scaly condition that develops on babies’ scalps and eyebrows in the first few months of life. When it also involves redness behind ears, armpits, neck folds, and groin area, it tends to be referred to as seborrheic dermatitis or seborrhea.

Many pediatricians encounter this at least 2- 4 times per day in their office. 40% of children in their first year of life have these issues. Prior to the creation of Happy Cappy Medicated Shampoo for Cradle Cap, 70% of pediatricians would suggest adult dandruff shampoos to fix this problem.

Anti-dandruff shampoo with zinc pyrithione and selenium sulfide were the two most common active ingredients suggested by pediatric clinicians. Happy Cappy is the first OTC (over-the-counter) product with an active ingredient for dandruff and seborrheic dermatitis made for a child. 

We made Happy Cappy Baby Shampoo for Cradle Cap so that pediatricians no longer had to suggest the use of adult shampoos with harsh chemicals for babies.

Our Happy Cappy Medicated Shampoo for Seborrheic Dermatitis and Dandruff shampoo can help reduce flaking, itching, and irritation associated with seborrheic dermatitis and dandruff in adults.

All Happy Cappy Products are free from skin-irritating harsh chemicals such as fragrances, parabens, sulfates, and phthalates, making them safe to use on all skin types and people of all ages. 

Why is Happy Cappy 0.95% Zinc Pyrithione Shampoo?

In 1986, companies that made 1% Pyrithione Zinc (PZ) wanted to be able to sell in foreign markets like Germany, where 0.95% was the max concentration. Data was reviewed by the FDA that showed similar improvements in scaling and determined that 0.95% vs. 1% was not apt to cause any decrease in product effectiveness [3]. 

In the Final Monograph, produced in 1991, the strength of PZ can be between 0.3-2% for dandruff and 0.95% and 2% for seborrheic dermatitis. Having a lower percentage of PZ can cause less dryness, yet it’s equally effective, which is why Dr. Eddie has used 0.95% zinc pyrithione in Happy Cappy products.

To make them safe to be used on people of all ages and skin types, even those with sensitive skin. 

Is Pyrithione Zinc Safe?

Pyrithione Zinc (PZ) is insoluble in water and not easily absorbed through the skin when topically applied or easily absorbed through mucous membranes if swallowed. Data from evaluated studies by the FDA showed that topically applied PZ has a high safety margin, no contact sensitization, and no photosensitization. From 1964 to 1982, only 3 cases of allergic contact dermatitis had been reported [4].

Happy Cappy Pyrithione Zinc Shampoo is Generally Regarded As Safe And Effective (GRASE).

GRASE is an FDA designation. In order to conclude a GRASE determination, a drug must satisfy three criteria. 1. The particular drug must have been subjected to adequate and well-controlled clinical investigations that establish the product as safe and effective. 2. Those investigations must have been published in the scientific literature available to qualified experts. 3. Experts must generally agree, based on those published studies, that the product is safe and effective for its intended uses.

At a minimum, the general acceptance of a product as GRASE must be supported by the same quality and quantity of scientific and/or clinical data necessary to support the approval of a new drug application.

Conclusion

Zinc pyrithione has been known as effective for decades in reducing itching, irritation, and flaking associated with dandruff and seborrheic dermatitis due to its antibacterial and antifungal properties. Various scientific studies have proven its effectiveness, and its FDA-approved status makes it a trusted active ingredient for managing scalp and skin conditions in both children and adults. 

This long history of safety, effectiveness, and widespread use by pediatricians influenced us to use it as an Active Ingredient for our Medicated Shampoo and Body Wash.

Medical References

• Federal Register of FDA (1982) “Proposed Rules” for “OTC Drug Products for the Control of Dandruff, Seborrheic Dermatitis and Psoriasis; Establishment of a monograph” p.54664-54666

• Understanding the dandruff scalp before and after treatment: an in vivo Raman spectroscopic study. – Bonnist EY, Pudney PD, Weddell LA, Campbell J, Baines FL, Paterson SE, Matheson JR., Int J Cosmet Sci. 2014 Aug;36(4):347-54. doi: 10.1111/ics.12132. Epub 2014 May 14

• Federal Register of FDA (1986) “Tentative Final Monograph” for “OTC Drug Products for the Control of Dandruff, Seborrheic Dermatitis and Psoriasis; Establishment of a monograph”p.27350-27351

• Above from: Federal Register of FDA (1982) “Proposed Rules” for “OTC Drug Products for the Control of Dandruff, Seborrheic Dermatitis and Psoriasis; Establishment of a monograph” p.54664-54666

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Dr. Eddie Valenzuela

Dr. Eddie Valenzuela is an award winning pediatrician and the founder and CEO of Pediatric Solutions, LLC.

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