The new antipsychotics. How much better are they?

BACKGROUND

Despite considerable efficacy, conventional antipsychotics cause debilitating extrapyramidal side effects and may worsen 'negative' symptoms of schizophrenia. New atypical antipsychotics (clozapine, risperidone, olanzapine) have become available, and quetiepine is expected shortly; it is TGA approved and is currently available to psychiatrists through a familiarization program.

OBJECTIVE

To inform general practitioners about the novel antipsychotics and their therapeutic role in contrast to conventional antipsychotic drugs.

DISCUSSION: The major benefit offered by atypical antipsychotics is that these drugs are less likely to cause distressing and disabling extrapyramidal side effects at therapeutically effective doses than conventional drugs. Advantages in terms of efficacy are marginal, though clozapine is superior to conventional drugs in treatment resistant patients. The new drugs are not without other side effects. Clozapine can cause agranulocytosis, needs ongoing haematological monitoring and is only available through specialist centres. However, the new drugs do improve overall outcome. Use of risperidone, olanzapine and quetiepine is now widely recommended in preference to conventional drugs, while clozapine is used when other drugs have failed.