Transdermal and dermal enhancing activity of pyrrolidinones in hairless mouse skin

The transdermal penetration-enhancing abilities of 16 pyrrolidinones were tested against the model drug hydrocortisone using a hairless mouse skin model in vitro. Skins were pretreated for I h with the enhancer in propylene glycol before application of the drug also in propylene glycol. Enhancement ratios (ER) were calculated for permeability coefficient (P), 24-h receptor concentration (Q(24)), and skin content of drug (SC) and compared to control values (no enhancer present). N-Dodecyl-2-pyrrolidinone and 2-pyrrolidinone-1-acetic acid dodecyl ester were found to produce the greatest enhancement for all the parameters calculated with ER for Q(24) of 23.11 and 11.68, respectively. These same enhancers also produced high ERs for P with 42.95 and 41.07, respectively. These values exceed Atone's enhancement ratios for the same parameters and hence these enhancers are candidates for further development as penetration enhancers. (C) 1997 Elsevier Science B.V.