Quetiapine long-term effects

Several modem, better-tolerated antipsychotic agents (olanzapine, quetiapine, and risperidone) have recently received FDA approval for use in acute mania. There is also evidence of antimanic efficacy for aripiprazole and ziprasidone. Olanzapine is FDA-approved for its long-term effectiveness in bipolar disorder 1. Other atypical antipsychotic drugs are under investigation for long-term prophylactic treatment of bipolar disorder. 

Ari pi prazole, olanzapine, quetiapine, risperidone, and ziprasidone are effective as monotherapy or as add-on therapy to lithium or valproate for acute mania. Prophylactic use of antipsychotics can be needed for some patients with recurrent mania or mixed states, but the risks versus benefits must be weighed in view of long-term side effects (e.g., obesity, type 2 diabetes, hyperlipidemia, hyperprolactinemia, cardiac disease, and tardive dyskinesia). 

Clozapine, risperidone, olanzapine, quetiapine, and ziprasidone have all been approved for the treatment of schizophrenia. Data from long-term open evaluations of clozapine demonstrate that improvement is maintained over time, even when the dose is reduced. Further, patients did not develop tolerance to its antipsychotic effect. Naturalistic reports indicate that an adequate trial for acute response in some patients may be at least 6 months. Further, a small number (8 of 14) of previously refractory patients were successfully maintained on clozapine for up to 2 years ( 215). 

The same group of antipsychotic drugs have been evaluated for their effects on working memory (276,277) in a visual spatial version of the delayed non-matching to position paradigm (278,279). Haloperidol and risperidone exhibit marked inhibitory effects in low doses, whereas considerably higher doses of clozapine, olanzapine, and ziprasidone are required to produce similar effects (276). Sertindole and quetiapine are inactive at the doses tested (276). Long-term treatment reveals a continued memory impairment of memory by haloperidol, the development of tolerance to the effects of clozapine on memory, and continued lack of impairment by sertindole (277). 

Chue P, MaUa A, Bouchard RH, Lessard S, Ganesan S, Stip E, SPECTRUM XR Study Group, et al. The long-term dinical benefit and effectiveness of switching to once-daily quetiapine extended release in patients with schizophrenia. Curr Med Res Opin 2013 29(3) 227-39. 

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