, Volume 235, Issue 1, pp 369–371 | Cite as

Botulinum toxin: a novel therapy for clozapine-induced sialorrhoea

  • Rohit Verma
  • Kuljeet Singh Anand
Letter to the Editor


Sialorrhea (“Drooling” or “Ptyalis” or “hypersalivation”) is an excess of salivary pooling in oral cavity leading to overflow of saliva from mouth. The prevalence of clozapine-induced sialorrhea (CIS) is about 30% (10–92%) that is much more than agranulocytosis, the major scare (Maher et al. 2016). It usually develops early in treatment with dose-related persistence and rare development of tolerance to this side effect (Yesilyurt et al. 2010). As a consequence to CIS, patients can develop hoarseness, dysphonia, cough, nocturnal awakening, sleep disorder, symptomatic aerophagia, bloating, gastrointestinal distress, and even cases of fatalistic aspiration pneumonia (Bird et al. 2011). It also leads to embarrassment culminating in social withdrawal, reduced self-esteem, and increased stigma. Both the medical and psychosocial consequences pave way towards reduced compliance to clozapine culminating in symptomatic deterioration in the patient (Yesilyurt et al. 2010; Bird et...


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2017

Authors and Affiliations

  1. 1.Department of Psychiatry, Teaching BlockAll India Institute of Medical SciencesNew DelhiIndia
  2. 2.Department of Neurology, Post Graduate Institute of Medical Education and ResearchDr. Ram Manohar Lohia HospitalNew DelhiIndia

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