RELATIONSHIP BETWEEN NEGATIVE SYMPTOMS IN CHRONIC-SCHIZOPHRENIA AND NEUROLEPTIC DOSE, PLASMA-LEVELS AND SIDE-EFFECTS

The negative symptoms of schizophrenia are often difficult to distingu ish from the side effects of antipsychotic medication. In this study, we tried to clarify this issue by studying a group of patients in a cl inic setting where a wide range of antipsychotic doses were being pres cribed. Thirty-one patients meeting DSM-III-R criteria for schizophren ia or schizoaffective disorder were studied. Clinical ratings were car ried out to assess the positive and negative symptoms of schizophrenia , parkinsonism, akathisia and tardive dyskinesia. Plasma levels were a lso measured for the majority of patients. Antipsychotic plasma levels were found to be highly correlated with dose. Antipsychotic dose and plasma levels were not correlated with the severity of negative sympto ms, akathisia or parkinsonism. However, the severity of positive sympt oms and tardive dyskinesia were positively correlated with both dose a nd plasma level. These findings do not support the hypothesis that hig her doses of antipsychotic medication are associated with more severe negative symptoms.