title: Safety evaluation of topical valproate application.
abstract: The potential role of topical valproate (VPA) in hair regrowth has been recently suggested. However, safety reports of VPA as a topical formulation are lacking. Therefore, in the present study, we investigated whether VPA causes skin irritation in humans. We first performed a cell viability test and showed that VPA did not exhibit toxicity toward HaCaT keratinocytes, fibroblasts, and RBL-3H mast cells. We then performed clinical patch test and skin irritation test through transdermal drug delivery with the help of microneedle rollers. No significant findings were obtained in the clinical patch test. In the skin irritation test, only 1 patient showed erythema at 1 hr, but the irritation reaction faded away within a few hours. Erythema and edema were not observed at 24 hr. We concluded that VPA has minimal potential to elicit skin irritation. Therefore, we consider that VPA can safely be applied to human skin.
authors.affiliation: Department of Dermatology, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Choi
authors.forename: Song Yi
authors.initials: SY
authors.lastname: Seop
authors.forename: Moo Yeol
authors.initials: MY
authors.lastname: Hyun
authors.forename: Kwang Ho
authors.initials: KH
authors.lastname: Yoo
authors.forename: Beom Joon
authors.initials: BJ
authors.lastname: Kim
authors.forename: Myeung Nam
authors.initials: MN
authors.lastname: Kim
authors.forename: Jae-We
authors.initials: JW
authors.lastname: Cho
keywords: Skin toxicity; Valproate