OBJECTIVES: The authors have intended to know the drug interaction of fluoxetine and haloperidol when coadministering two drugs to the chronic schizophrenics by assessing the changes of positive, negative symptoms and extrapyramidal symptoms. METHOD: We selected 38 patients, the chronic schizophrenics with no physical problems. they are randomly assigned to placebo group and drug group. And then, placebo or fluoxetine 20mg were administered to the subjects of each group during 8 week period. We have assessed their psychopathology and extrapyramidal symptoms using positive and Negative Syndrome Scale(PANSS), Clinical Global Impression(CGI), Simpson-Angus Scale at o, 2, 4, 6, 8 week during the period. RESULTS: 38 patients have completed the study during 8 week. 1) PANSS, CGI : no significant difference between groups and no significant change according to the times. 2) Simpson-Angus Scale : no significant changes. CONCLUSION: When co-administering fluoxetine and haloperidol, there were no significant changes of psychopathology and extrapyramidal symptoms. There results suggest that it is safe to coadminister fluoxetine to schizophrenic with haloperidol treatment.
Drug Interactions ; Fluoxetine* ; Haloperidol* ; Humans ; Psychopathology*

The selective serotonin reuptake inhibitor fluoxetine is one of the most frequently prescribed drugs for the treatment of depression and other psychiatric disorders. In the few years, there have been several reports of adverse effects encountered during coadministration of fluoxetine with or without other psychotropic drugs. We experienced three cases of extrapyamidal symptoms were developed when administered fluoxetine alone and with neuroleptics. We conclude that there is a probable or possible causal relationship between fluoxetine and extrapyramidal side effects. The pathogenesis of such adverse reactions, which may be hetero-geneous, is unknown, but it has been suggested that they might be caused by serotonergically mediated inhibition of dopaminergic transmission. From reports in those cases, it appears that fluoxetine alone may be associated with extrapyramidal side reactions. Furthermore the potential for increased levels of concomitant psychotropic medicines and increased side effects, should be borne in mind.
Antipsychotic Agents ; Depression ; Fluoxetine* ; Psychomotor Agitation ; Psychotropic Drugs ; Serotonin