CYP3A5 and End Stage Liver Disease: Pathogenesis involved in neurotoxicity is not fully understood but includes the disruption of the blood-brain barrier and the predisposing factors such as drug exposure, twice-daily dosing, CYP3A5 polymorphisms, older age, female sex, Black ethnicity, high model for end-stage liver disease (MELD) scores, pretransplant hemoglobin, and inflammatory markers such as C-reactive protein (CRP).