P&G promotes piroctone olamine for healthy scalp microbiome and dandruff control

12 Jan 2024 --- Procter & Gamble (P&G) researchers demonstrate the effectiveness of piroctone olamine (PO) shampoo to help combat dandruff and achieve a healthier scalp microbiome.

PO is a compound sometimes used to treat fungal infections due to its anti-fungal properties and is found in P&G’s Head & Shoulders dandruff control hair products. 

Researchers believe part of the aetiology of dandruff can be attributed to an “imbalance” associated with the scalp microbiome’s disease. They further state PO treatment can restore a healthier microbiome, reduce oxidative stress and promote better scalp health.

Dandruff reduction
Malassezia globosa is the root cause of dandruff and part of the Malasseziaceae family of fungi.  The P&G study reveals a higher relative abundance of Malassezia restricta and Staphylococcus capitis and a lower abundance of Cutibacterium acnes associated with the dandruff scalps relative to the no-dandruff scalps.

PO shampoo shows to be create a healthy, no-dandruff scalp microbiome.A three-week PO shampoo treatment reduced the relative abundance of Malassezia species and Staphylococcus capitis and increased the relative abundance of Cutibacterium acnes. This change to the scalp microbiome composition is consistent with a return to a healthy, no-dandruff microbiome and improved clinical signs and symptoms as measured by adherent scalp flaking score compared with the control shampoo. 

Functional genomics analysis showed that the PO shampoo treatment reduced oxidative stress-associated genes. These changes correlated positively to improvements in dandruff severity. PO treatment favorably shifted scalp microbiomes in dandruff subjects toward the no-dandruff state.

Scalp microbiome
The study sought to characterize the scalp microbial composition, function and connection to dandruff severity using a metagenomics approach — a culture-independent method that allows the identification and characterization of organisms from all kinds of samples — to understand the impact of a PO-containing anti-dandruff shampoo on the scalp microbiome.

The researchers used shotgun metagenomics, which allows researchers to comprehensively sample all genes in all organisms present in a given complex sample, to characterize the composition of the scalp microbiomes from 94 subjects with and without clinically defined dandruff. 

The microbiome of the scalps of 100 dandruff “sufferers” before and after three weeks of treatment with either control or anti-dandruff shampoo containing 0.5% PO was characterized and compared to identify microorganisms associated with the dandruff condition and the related pathways and processes that may contribute to PO’s effect on scalp microbiome.

The research is published in the Wiley Online Library.

By Sabine Waldeck