P10.135 AN INVESTIGATION OF THE IMPACT OF ZPT CONTAINING ANTI-DANDRUFF SHAMPOOS ON SCALP IRRITATION AND ITCH ASSOCIATED WITH DANDRUFF

Kathy M. Kerr, Dr. James R. Schwartz (PhD), Dianna C. Kenneally, Carl H. Margraf

The Procter & Gamble Company, Cincinnati, Ohio, USA

Objectives: In addition to scalp flaking and desquamation, itch and irritation are significant symptoms associated with dandruff and seborrheic dermatitis. While, ZPT containing shampoos have been definitively shown as efficacious against flaking, recent research studies were performed to determine the efficacy of ZPT containing shampoos on itch and irritation symptoms associated with dandruff.

Methods: A series of in-vitro Interluken-1alpha Production (IL-1alpha) studies were performed to evaluate the amount of IL-1alpha produced following exposure of a model cell system to various shampoo products. IL-1alpha is an inflammatory cytokine produced by a cell and is believed to trigger an irritation response in the human brain. The quantification of IL-1alpha production in an in-vitro model cell system is an established industry standard for measuring consumer perceived irritation severity. In addition, clinical studies among dermatologist assessed moderate and severe dandruff/seborrheic dermatitis sufferers were conducted to evaluate the reduction in itch severity following 1% ZPT shampoo usage.

Results: IL-1alpha studies were performed to evaluate the impact of both anti-fungal (e.g. ZPT) and cosmetic shampoos on irritation.  Results showed the 1% platelet ZPT containing shampoos significantly reduced IL-1alpha production, thereby reducing irritation.

Self-perception results from two clinical studies were analyzed to determine the impact of 1% ZPT shampoo usage among dermatologist assessed dandruff sufferers. Results showed a significant reduction in self-perceived itch severity for participants with moderate and severe dandruff/seborrheic dermatitis after three and six weeks of 1% platelet ZPT shampoo usage.  This is compared to those who used a cosmetic shampoo for the same time period.

Conclusions: The use of a 1% platelet ZPT shampoo reduces production of the marker responsible for irritation (IL-1alpha) and results in a consumer meaningful reduction in scalp itch and irritation associated with dandruff and seborrheic dermatitis.