Olanzapine transfer by human placenta

1. The present study assessed the human transplacental transport of olanzap ine, a new antipsychotic drug effective in the treatment of schizophrenia. 2. Using the normal-term placenta perfused single cotyledon system, we show that: (i) 5-14% of labelled olanzapine crosses from the maternal to foetal compartments in 4 h; (ii) transport depends significantly on binding chara cteristics, especially of albumin; (iii) no oxidative metabolites of olanza pine appear in the placental perfusate over 4 h; and (iv) approximately 17% of olanzapine, on average, is converted to the glucuronide, which is trans ferred by the placenta at a rate slightly slower than the parent drug.