A COMPARATIVE IN-VITRO STUDY OF TRANSDERMAL ABSORPTION OF ANTIEMETICS

Transdermal absorption of a series of antiemetics (alizapride, bromopr ide, clebopride, domperidone, metoclopramide, metopimazine, and scopol amine) was studied in vitro with the skin of hairless rats as the memb rane. The aim of the study was to determine the permeation parameters [transdermal permeability rate constant (K-p), lag time, and flux] as a measure of the intrinsic permeability of these drugs across the skin , with a view to predicting their potential therapeutic formulation in Transdermal Therapeutic Systems. A linear correlation was established between the log K-p values corresponding to the antiemetics studied a nd their melting point (r = 0.8120, p < 0.05). The logarithm of K-p fo r the antiemetics studied can be predicted from the logarithm of the i ntrinsic partition coefficient (n-octanol-water) by a parabolic functi on (r = 0.9284, p < 0.01). Bromopride showed the shortest lag time (19 .73 h), whereas clebopride was the most suitable drug as a candidate f or formulation in transdermal delivery systems.