From: http://psychiatricresourceforum.blogs.com/my_weblog/2006/05/index.html

Few words in psychiatry have caused as much heat - yet generated so little light - as the term “atypical” antipsychotic. Originally a mistranslation of a German word, the word was simply a marketing tool that eventually developed a life of its own. The newer antipsychotics like clozapine, risperidone, quetiapine, olanzapine, ziprasidone, aripiprazole and bifeprunox do have some similarities in how they work, but also many differences. Many have quite different chemical structures and even work in different regions of the brain. That is to say nothing of differences in side-effect profiles. This criticism of the term “atypical” is not an idle semantic debate. To use the term to describe such different medicines is really a little sloppy. It makes us think that the medicines are interchangeable, when every clinician knows that they are not. And it makes us think that the side effect profiles are much the same, which again is manifestly not the case. Finally, we all know that restricted formularies are coming, and it can be very difficult for our patients, if they have trouble in trying different options. For we also all know that there is never one medicine that will work for everyone.

There is a most welcome and excellently reasoned article on this important topic by Wolfgang Fleischhacker and Christian Widschwendter, from the Medical University in Innsbruck in Austria. Wolfgang has been a leading light in European psychopharmacology for many years, and his opinions are always worth reading.

Their review re-emphasizes the point that the new generation of antipsychotic medicines has many fundamental differences in terms of efficacy, safety and tolerability, of drugs with different efficacy/safety/tolerability profiles. As every clinician knows there are large inter-individual variations in peoples’ responses to these medications.

We still are not good at predicting who will respond to what medicine. However advances in genetics and brain imaging, and also in our understanding about which medicine is best for what constellation of symptoms – particularly cognitive problems - are helping move the field forwards.