title: Onychopharmacokinetics of terbinafine hydrochloride penetration from a novel topical formulation into the human nail in vitro.
abstract: This study determined the onychopharmacokinetics, nail absorption, distribution, and penetration of [¹⁴C]-terbinafine HCl in a new topical formulation into/through the human finger nail using the in vitro finite dose model. This study determined the penetration rate of terbinafine HCl from multiple doses of topical formulation applied daily for 14 days. Results showed that the total dose recovery (mass balance) was almost 100%. The concentration of terbinafine HCl in the deeper nail plate (ventral/intermediate layers) and the cotton-pad nail bed samples after the 14-day treatment were 613 ± 145 and (±S.D.) and 27 ± 1.2 µg/cm³ (or 1.9 ± 0.6 µg/cm³ daily) on average, respectively. In comparison with nail concentration data from the literature for other topical terbinatine formulations, our results show that higher amounts of terbinafine HCl reached the deep nail plate and/or the nail bed after a 14-day topical treatment with this topical formulation in vitro.
authors.affiliation: Department of Dermatology, University of California San Francisco, San Francisco, CA, USA. huix@derm.ucsf.edu
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Hui
authors.forename: Åke
authors.initials: Å
authors.lastname: Lindahl
authors.forename: Sonia
authors.initials: S
authors.lastname: Lamel
authors.forename: Howard I
authors.initials: HI
authors.lastname: Maibach
mesh_terms: D000042:Absorption; D000287:Administration, Topical; D000327:Adsorption; D000328:Adult; D000935:Antifungal Agents / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D002250:Carbon Radioisotopes; D055598:Chemical Phenomena; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D009262:Nails / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D009281:Naphthalenes / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D010539:Permeability; D013499:Surface Properties; D000077291:Terbinafine
chemical_list: D000935:Antifungal Agents; D002250:Carbon Radioisotopes; D009281:Naphthalenes; D000077291:Terbinafine