ABSTRACT
Over the past 14 years, atypical antipsychotic drugs exemplified by clozapine (1) have revolutionized the treatment of schizophrenia (2-4, 125). Despite the fact that atypical antipsychotic drugs are now prescribed more commonly than typical antipsychotic drugs in many areas of the world, there continues to be debate regarding the cost-effectiveness (5) and the clinical superiority of atypical antipsychotic drugs (6). Atypical antipsychotic drugs are distinguished from typical antipsychotic drugs by the following criteria: 1) atypical antipsychotic drugs lack extrapyramidal side effects (EPS) in humans; 2) atypical antipsychotic drugs do not elevate serum prolactin levels in humans; and 3) atypical antipsychotic drugs do not induce catalepsy in rodents. Other studies suggest that atypical antipsychotic drugs reduce suicidality (7) and improve cognition (8) for instance, though not necessarily without serious side effects such as weight gain (9) and other metabolic and cardiovascular side effects (10,11).
