Evaluating the effect of risperidone on speech: A cross-sectional study

• We compared speech characteristics of patients on risperidone with control group.
• Those on risperidone had reduced maximum phonation duration and increased s/z ratio.
• Diadochokinetic rate as well as lingual and labial speech subsystems was deficient.
• Intelligibility of speech was also reduced.
• These are independent of extrapyramidal symptoms and tardive dyskinesia.

Speech subsystems are susceptible to the effects of several factors including medications. The atypical antipsychotics can also adversely affect the speech because of its action on serotonin and dopamine neurotransmitters. The present study aims to analyze the speech characteristics associated with atypical antipsychotic risperidone. Speech of 92 patients on risperidone with or without trihexyphenidyl and/or clonazepam were compared with that of 31 persons who were not on any psychotropic medicines. Compared to control group, maximum phonation duration, sequential motion rate of diadochokinesia was reduced by about 3 s and 1 syllable/s respectively and s/z ratio was increased by 0.16 in patients with risperidone. Performance of larynx, lips and tongue sub-system and intelligibility of speech were also significantly reduced in risperidone group. Risperidone did impact the phonation and articulation sub-systems of speech mildly, which was independent of tardive dyskinesia and extrapyramidal symptoms. Randomized controlled prospective study looking into impact on speech and related effect on drug adherence, functioning and quality of life needs to be conducted with risperidone and other atypical antipsychotics.