Comparing the side effect profile of the atypical antipsychotics

West Afr J Med. Oct-Dec 2002;21(4):313-5. doi: 10.4314/wajm.v21i4.28008.


Typical antipsychotics exert their effect by blocking post-synaptic dopaminergic receptors; blockade of the mesolimbic and mesocortical pathways are therapeutic and help reduce positive psychotic symptoms but blockade of the nigro-striatal pathway produces extrapyramidal side effects (EPSE). Post clozapine, the Food and Drug Administration (FDA) has approved the use of four newer atypical antipsychotics; risperidone, olanzapine, quetiapine and ziprasidone for the treatment of schizophrenia. Because of their dual serotonin and dopamine receptor blocking abilities, atypical antipsychotics have greater efficacy (especially for negative symptoms) and fewer EPSE when compared to the typical antipsychotics. Given the lack of studies directly comparing these agents, we used the Physician Desk Reference (PDR) to calculate the treatment emergent placebo adjusted side effects for these atypical antipsychotics. The results are then presented in an easy to read table. To the best of our knowledge, this is the first comparison study involving these four newer antipsychotic agents.

Publication types

  • Comparative Study
  • Review

MeSH terms

  • Antipsychotic Agents / adverse effects*
  • Antipsychotic Agents / chemistry
  • Benzodiazepines
  • Cardiovascular Diseases / chemically induced
  • Central Nervous System Diseases / chemically induced
  • Dibenzothiazepines / adverse effects*
  • Dibenzothiazepines / chemistry
  • Dopamine Antagonists / adverse effects*
  • Dopamine Antagonists / chemistry
  • Gastrointestinal Diseases / chemically induced
  • Humans
  • Olanzapine
  • Patient Selection
  • Piperazines / adverse effects*
  • Piperazines / chemistry
  • Pirenzepine / adverse effects*
  • Pirenzepine / analogs & derivatives*
  • Pirenzepine / chemistry
  • Quetiapine Fumarate
  • Respiratory Tract Diseases / chemically induced
  • Risperidone / adverse effects*
  • Risperidone / chemistry
  • Schizophrenia / drug therapy
  • Serotonin Antagonists / adverse effects*
  • Serotonin Antagonists / chemistry
  • Thiazoles / adverse effects*
  • Thiazoles / chemistry
  • Treatment Outcome
  • Weight Gain / drug effects


  • Antipsychotic Agents
  • Dibenzothiazepines
  • Dopamine Antagonists
  • Piperazines
  • Serotonin Antagonists
  • Thiazoles
  • Benzodiazepines
  • Quetiapine Fumarate
  • Pirenzepine
  • ziprasidone
  • Risperidone
  • Olanzapine