Treatment of Clozapine-Associated Sialorrhea: The Role of Benzamide Derivatives

A systematic chart review of pharmacological interventions in patients with clozapine-induced hypersalivation

OBJECTIVES

To investigate the efficacy and tolerability of medications, such as mouthwash use of 1 % atropine sulfate and tropicamide drops, oral amitriptyline and amisulpride used for clozapine-induced hypersalivation (CIH).

METHODS

The medical charts of inpatients with psychotic disorders between 2010 and 2022 were reviewed retrospectively. We detected 161 patients with eligible data who received or commenced clozapine. Primary outcome was defined as the percentage change in the diameter of a wet patch on the pillow (DWP) for improvements in CIH.

RESULTS

The frequency of CIH was 42 % (n = 68). The first step medications for CIH were tropicamide drops (49 %), atropine drops (43 %) and amitriptyline (3 %). After the first step, the median DWP significantly decreased by -33 %. During the index hospitalization, in 18 patients with persistent CIH, the median DWP significantly decreased by -42 % with the second step medications which also included amisulpride. There were no reported serious adverse events. The change in DWP was significantly correlated with the duration of clozapine treatment (r = 306) and clozapine serum level at discharge (r = 0.294). A linear regression model showed a link between the change in DWP and reduced Positive and Negative Syndrome Scale scores.

CONCLUSIONS

Our findings emphasize that mouthwash use of atropine or tropicamide drops has a satisfying and tolerable effect in treating CIH. Switching medications for CIH seems to be effective when CIH persists despite a first step agent. Controlled follow-up studies are needed to understand the relationship between CIH, clozapine serum levels, illness severity, and functioning.

Rethinking Clozapine: Lights and Shadows of a Revolutionary Drug

The current literature globally highlights the efficacy of Clozapine in several psychiatric disorders all over the world, with an FDA indication for reducing the risk of repeated suicidal behavior in patients with schizophrenia or schizoaffective disorder. A growing field of research is also stressing a possible broader beneficial effect of Clozapine in promoting neuroprotection and neurotrophism. However, this drug is linked to several life-threatening side effects, such as agranulocytosis, myocarditis and seizures, that limit its use in daily clinical practice. For this work, a search was performed on PubMed using the terms "Clozapine indications", "Clozapine adverse effects", "Clozapine regenerative effects", and "Clozapine neuroplasticity" with the aim of reviewing the scientific literature on Clozapine's treatment indications, adverse effects and potential regenerative role. The results confirmed the efficacy of clozapine in clinical practice, although limited by its adverse effects. It appears crucial to raise awareness among clinicians about the potential benefits of using Clozapine, as well educating medical personnel about its risks and the early identification of possible adverse effects and their management.

Evaluation and Comparison of the Effectiveness of Atropine Eye Drops, Ipratropium Bromide Nasal Spray, and Amitriptyline Tablet in the Management of Clozapine-Associated Sialorrhea in Patients With Refractory Schizophrenia: A Randomized Clinical Trial

PURPOSE

Clozapine, a second-generation antipsychotic medication, is mainly indicated for managing treatment-resistant schizophrenia. Among all the nonthreatening adverse effects of clozapine, sialorrhea is a stigmatizing complication occurring in approximately 31.0% to 97.4% of patients. In this study, 2 topical agents (atropine eye drop and ipratropium nasal spray) and a systemic medication (amitriptyline) were compared simultaneously for the management of clozapine-associated sialorrhea.

METHODS

We conducted a randomized, single-blinded, non-placebo-controlled clinical trial from June 2022 to January 2023. Eligible patients were randomly allocated into 3 mentioned groups. Patients were monitored for sialorrhea weekly based on scales, including the Toronto Nocturnal Hypersalivation Scale, Clinical Global Impression-Improvement, and Clinical Global Impression-Severity for 1 month. Possible adverse drug reactions and adherence were also recorded.

RESULTS

Twenty-four patients, including 6, 10, and 8 individuals in ipratropium bromide nasal spray, atropine eye drop, and amitriptyline groups, completed the study, respectively. The cohort's demographic, baseline clinical, and sociocultural characteristics were comparable among the 3 groups. Within-group comparisons, between times baseline and week 4, demonstrated that significant differences were in groups atropine and amitriptyline based on Toronto Nocturnal Hypersalivation Scale, in 3 groups based on Clinical Global Impression-Improvement, and also in only-atropine group based on Clinical Global Impression-Severity. Likewise, between-group comparisons showed that atropine was significantly more effective in clozapine-associated sialorrhea management than amitriptyline and ipratropium, in the first 2 weeks and second 2 weeks of study, respectively. Regarding safety, the interventions were tolerated relatively well.

CONCLUSIONS

Conclusively, atropine is more efficacious than amitriptyline, within the first 2 weeks of study and also relative to ipratropium, overall. As time effect was significant between atropine and amitriptyline, according to analysis of covariance test, further investigation with longer follow-up duration would be prudent. In addition, expanding patient population with larger sample size should be conducted for more precision.