Olanzapine: preclinical pharmacology and recent findings

Olanzapine possesses a broad pharmacological profile, interacting with a ra nge of different neurotransmitter receptors. Although its affinity for musc arinic receptors is relatively greater than for dopamine receptors, on sche dule-controlled behaviour olanzapine displays a profile resembling a dopami ne antagonist. Likewise, in a test of cognitive function, olanzapine does n ot produce anticholinergic-like deficits. In drug discrimination assays, ol anzapine substitutes for clozapine in clozapine-trained animals and clozapi ne generalises to olanzapine in olanzapine-trained animals. Olanzapine also reverses the behavioural deficits produced by inhibiting N-methyl-D-aspart ate receptor glutamatergic transmission. This profile suggests that olanzap ine will be effective against both positive and negative symptoms of schizo phrenia while producing minimal extrapyramidal side-effects.