The latest results from the European First Episode Schizophrenia Trial (EUFEST) show that when it comes to improving cognition in patients with schizophrenia, there is little difference between antipsychotic agents.
The randomized trial shows that a relatively low dose of haloperidol, a first-generation antipsychotic, is as effective as 4 second-generation antipsychotics, including amisulpride, olanzapine, quetiapine, and ziprasidone in moderately improving cognition among patients experiencing a first episode of schizophrenia.
So, if you are a doctor trying to decide which antipsychotic to use in order to 'restore' the cognition in your patients, 'generation' thingy, is not a point anymore. It will be more to pharmacoeconomic, and side effects.
Talking about side effects, earlier this year, there's a study shows that all second-generation drugs induced fewer extrapyramidal adverse effects than haloperidol (even at low doses), but only clozapine, olanzapine, and risperidone had induced fewer extrapyramidal adverse effects than low-potency, first-generation antipsychotics.
Which means, the classification of first and second generation antipsychotics, is actually confusing and should be abandoned. Actually, the so-called 'second generation antipsychotics' differ in many properties, including efficacy, side effects, cost, and pharmacology, they do not form a homogeneous class, and, basically, neither do first-generation drugs.
So, the glamorous bubbles created by pharmaceutical companies on second generation antipsychotics, is bursting, like the economy in Wall Street.
Time for us to think about the newer drugs in the market, all the so-called more superior drugs than the older one. Are they all as effective as the companies claimed?
Davidson et al. Cognitive effects of antipsychotic drugs in first-episode schizophrenia and schizophreniform disorder: a randomized, open-label clinical trial (EUFEST). Am J Psychiatry 2009; 166: 675-682
LeuchtS, CorvesC, ArbterD, EngelRR, LiC, DavisJM. Second-generation versus first-generation antipsychotic drugs for schizophrenia: a meta-analysis. Lancet200810.1016/S0140-6736(08)61764-X.