Objective: Sialorrhea (hypersalivation) is a common side effect occurring in 31−54% of patients receiving clozapine therapy. It usually develops early in the course of treatment and is more prominent at night.(1)There are limited numbers of previous studies of amisulpiride add-on for the treatment of clozapine-induced hypersalivation (CIH) To our knowledge here we present the first long-term study such 60 days in literature (1−3).
Methods: Nine patients with schizophrenia, receiving clozapine, had CIH. Amisulpiride (100 400 mg/day) was administered in addition to ongoing clozapine treatment (clozapine:100 mg/d to 400 mg/d). Nocturnal hypersalivation was recorded using the 5-point Nocturnal Hypersalivation Rating Scale (NHRS)(4). The NHRS was administered six times over a 60 day period; at baseline, after 7, 14, 28, 42 and 60 days. Statistical comparison of baseline, 7−14−28−42−60 day follow-up values was done using analysis of variants with repeated measures (one-way-ANOVA). Results were reported in mean values with standard
deviations.
Results: At the end of the trial, following 60 days of sulpiride treatment a linear reduction in the level of CIH was reported as measured by NHRS scores. Mean (±S.D.) baseline scores were 3.22 (0.66). Mean (±S.D.) scores following 7 days of treatment were 1.77 (1.09). The difference was not significant at first week (p: 0.051) but at the following weeks a significant amelioration was shown (p < 0.05). Mean (±S.D.) scores following 60 days of treatment were 0.4 (0.5) [F(8,526), p < 0.05]. None of the patients reported specific side effects except one patient who complained of sedation and dropped out at the 28. days of study. Other measures included the Scale for the Assessment of Positive Symptoms, the Scale for the Assessment of Negative Symptoms, Clinical Global ImpressionScale and Simpson-Angus Scale, weight, prolactin level. With amisulpride addon treatment, there was a significant increase in the prolactin level as an indicator of compliance but the results of other scales were not significant.
Conclusion: CIH is a common and socially stigmatizing side effect, which results in poor treatment compliance. Our findings suggest that amisulpiride addition to clozapine therapy may ameliorate CIH. In this preliminary study we examined the effect of amisulpiride addition on CIH in a small sample size. A larger sample sized study is presently being performed to further investigate the clinical results of combined therapy both on hypersalivation and on other parameters.