Antipsychotic agents. Gradually improving treatment from the traditional oral neuroleptics to the first atypical depot

Abstract

Relapse is one of the key factors in the long-term outcome of schizophrenia. The consequences of relapse are diverse and often unpredictable, and the time to recovery and degree of recovery worsen with each successive relapse. There is now overwhelming evidence that advances in antipsychotic drug treatment have led to significant reductions in the rate of relapse. This review charts the developments that have taken place in antipsychotic therapy from the introduction of depot formulations, through atypical agents, to the development of the first long-acting atypical antipsychotic. Depot formulations of conventional antipsychotics were developed in the 1960s and led to fewer relapses and episodes of hospitalization, compared with oral equivalents. Meta-analysis has confirmed that patients receiving depot antipsychotics experience significantly greater global improvement than those receiving the respective oral agents. Conventional antipsychotics are, however, associated with a range of potentially serious adverse events. The atypical antipsychotics were introduced in the 1990s and have significant advantages over conventional agents with regard to positive and negative symptoms. There is also evidence that atypical agents can reduce the risk of relapse. Importantly, atypical antipsychotics have an improved safety profile compared with older agents, particularly with regard to extrapyramidal symptoms. One disadvantage of atypical agents has been that they are only available in an oral form. The recent development of a long-acting injectable formulation of risperidone means that a new treatment option is available to physicians.