There have been scattered reports of mild states of agitation induced by novel antipsychotic agents, in particular disturbed affect during a switch study of risperidone (Ashleigh & Larsen, 1998) and doubtless other cases which have never been reported. At least 19 cases have been reported of risperidone-induced mania (Lane et al, 1998; Zolezzi & Badr, 1999). Fitzgerald et al (1999) reported a case of olanzapineinduced mania and state that only one similar report existed previously. A Medline search revealed six other cases in the past five years (further details available from the author upon request) and to this series we now add an eighth.
A 55-year-old woman with a 20-year history of chronic anxiety and recurrent depressive episodes developed subjective excitement, increased psychomotor activity, insomnia, irritability and racing thoughts within three days of being prescribed olanzapine 2.5 mg nocte. Her condition rapidly normalised on cessation of olanzapine. There were no features suggestive of akathisia. It should be noted that this case may be slightly weakened by a previous manic episode some 20 years previously.
There have been a small number of reports to the manufacturers' adverse-events database (manufacturers' personal communications) for sertindole, quetiapine and amisulpride where the induction of manictype symptoms following commencement of the drugs has been a possibility but direct causal effect could not be established with certainty. No such reports could be found in the literature or by application to the manufacturers in respect of clozapine. Clozapine has been cited as having moodstabilising properties in bipolar affective states (Suppes et al, 1999).
The attribution of manicogenic properties to risperidone, olanzapine, sertindole, quetiapine and amisulpride suggests some shared pharmacological characteristics between these agents and most antidepressants, although amisulpride does not bind to serotonin receptors. We conclude that states of agitation, sometimes severe enough to resemble mania, although infrequent, may be a complication of some, if not all, novel antipsychotic agents with the possible exception of clozapine.