Positive versus negative symptoms in schizophrenia: response to haloperidol

1. Clinical response to treatment with haloperidol was studied in 20 schizophrenic inpatients with acute exacerbation (DSM-IIIR). 2. Patients were assigned to fixed doses of haloperidol (10, 20 or 30 mg/day) for three weeks. Clinical assessment was made using scales SAPS, SANS, BPRS and Simpson-Angus Scale for rating of extrapyramidal side effects. 3. Sixteen patients showed forty per cent or more decrease in positive symptoms assessed by SAPS, being considered the group of responders. Six out of the twenty patients showed improvement in negative symptoms assessed by SANS (improvement above 30%). 4. Clinical predictors of response were only identified for SAPS. The group of responders showed higher basal scores in total scale and formal thought disorder. 5. Negative symptoms responsive to treatment were affective flattening and alogia. Improvement in negative symptoms was independent from that in positive ones. 6. Socio-demographic predictors of clinical response were not found. No differences in clinical response were found in relation to the dose administered. 7. The results of our study suggest that negative symptomatology improves in a scheduled treatment with haloperidol. Assessment of negative symptoms may be useful in the evaluation of treatment of acute schizophrenia.