Possible induction of mania and hypomania by olanzapine or risperidone: a critical review of reported cases.
BACKGROUND
Risperidone and olanzapine are atypical antipsychotics that are now widely used in clinical practice.


METHODS
A MEDLINE search (1966-1999) showed that, following the introduction of these agents in recent years, 26 cases of induced hypomanic and manic syndromes have been reported during standard olanzapine (N = 10) or risperidone (N = 16) treatment.


RESULTS
A critical analysis of these case reports reveals that the effects on mood were sometimes insufficiently documented and that in about half of them (N = 16) evidence is highly suggestive of a causative role of risperidone or olanzapine in the induction of (hypo)manic symptomatology.


CONCLUSIONS
Despite limitations, the available literature confirms intriguing effects of these 2 antipsychotics on mood. The risk factors as well as the mechanisms of action underlying these effects remain to be clarified.
Aubry
J M
JM
Département de Psychiatrie, Clinique de Psychiatrie adulte 2, Chêne-Bourg, Geneva, Switzerland. jaubry@worldcom.ch
Simon
A E
AE
Bertschy
G
G
D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001569:Benzodiazepines; D001714:Bipolar Disorder / Q000139:chemically induced* / Q000453:epidemiology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077152:Olanzapine; D010890:Pirenzepine / Q000009:adverse effects* / Q000031:analogs & derivatives* / Q000627:therapeutic use; D011618:Psychotic Disorders / Q000188:drug therapy; D018967:Risperidone / Q000009:adverse effects* / Q000627:therapeutic use; D012559:Schizophrenia / Q000188:drug therapy
D014150:Antipsychotic Agents; D001569:Benzodiazepines; D010890:Pirenzepine; D018967:Risperidone; D000077152:Olanzapine