Evidence of lowest brain penetration of an antiemetic drug, metopimazine, compared to domperidone, metoclopramide and chlorpromazine, using an in vitro model of the blood-brain barrier.

Purpose: The objective of the current study was to determine the ability of some antiemetic compounds to cross the blood-brain barrier (BBB) and thereby to determine possible side effects of compounds for the central nervous system (CNS).

Methods: We compared the brain penetration of some antiemetic compounds using an in vitro BBB model consisting in brain capillary endothelial cells co-cultured with primary rat glial cells.

Results: This study clearly demonstrated that the metopimazine metabolite, metopimazine acid, has a very low brain penetration, lower than metopimazine and even less than the other antiemetic compounds tested in this study.