Scalp application of the antioxidant piroctone olamine reduces hair shedding in an 8-week randomized, double-blind, placebo-controlled clinical study

Int J Cosmet Sci. 2021 Nov:43 Suppl 1:S26-S33. doi: 10.1111/ics.12737.


Objective: Increasing scalp hair fullness is a global unmet consumer need. An approach to decrease hair shedding by reducing scalp stratum corneum oxidation via a combination of antioxidant and barrier-enhancing technologies has been previously demonstrated. The purpose of this study was to test the effectiveness of the individual antioxidant piroctone olamine in two different product forms (shampoo or leave-on product) for activity to improve hair retention.

Methods: Female subjects with self-perceived hair thinning participated in an 8-week, double-blind, placebo-controlled, randomized clinical study to evaluate either a piroctone olamine (PO) containing shampoo or a PO containing leave on treatment, each relative to their corresponding placebo formulation Too many periods. Results for phototrichograms, TEWL, and biomarker analysis of scalp condition for the shampoo treatments are discussed. Phototrichogram results are shared for the assessment of the leave on treatment.

Results: Statistically significant increases in hair amount were observed by phototrichogram after use of both PO-containing products versus placebo formulations. The PO shampoo treatment also significantly decreased oxidative stress on the hair and scalp, and improved scalp condition as assessed by TEWL and scalp biomarker values.

Conclusion: These results illustrate the effectiveness of a cosmetic antioxidant to improve scalp condition thereby improving hair retention. The observed improvements in scalp condition are consistent with previous reports with other antioxidant technologies and suggest that the hair retention effect was achieved by preventing oxidative damage to the scalp.

Keywords: antioxidant; hair growth; hair loss; hair shedding; hair treatment; scalp; skin barrier.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Administration, Topical
  • Adult
  • Aged
  • Alopecia / drug therapy*
  • Antioxidants / administration & dosage
  • Antioxidants / therapeutic use*
  • Double-Blind Method
  • Drug Combinations
  • Ethanolamines / administration & dosage
  • Ethanolamines / therapeutic use*
  • Female
  • Hair Preparations / administration & dosage
  • Hair Preparations / therapeutic use*
  • Humans
  • Middle Aged
  • Pyridones / administration & dosage
  • Pyridones / therapeutic use*
  • Scalp / drug effects*


  • Antioxidants
  • Drug Combinations
  • Ethanolamines
  • Hair Preparations
  • Pyridones
  • piroctone olamine

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