Clinical correlates of sialorrhea in clozapine patients

Objective: Sialorrhea occurs more frequently in patients on clozapine than in those on other antipsychotics and has an adverse impact on the quality of life. We evaluated clinical correlates of sialorrhea. Method: 79 patients with schizophrenia (54 males, 25 females; mean age 43.3 years, SD=12.7) from an urban clozapine clinic participated. Their total daily 24 hour dose of clozapine ranged from 100 to 650mg with the average at 341.8, SD=133.1). The part administered at nighttime ranged from 25 to 600mg, with the average at 258.7, SD=106.7. Results: The scores on Nocturnal Hypersalivation Rating Scale (NHRS) ranged from 0 to 4 with the average at 1.7, SD=1.2. The symptom was absent in 17.7%, minimal in 36.7%, mild in 15.2%, moderate in 21.5%, and severe in 8.9% of patients. The intensity of sialorrhea was not significantly correlated to the daily clozapine dose, or its nighttime part, or duration of clozapine treatment, age, and gender. The presence of concurrent other antipsychotics slightly increased the NHRS scores (r=.37) and the presence of antihypertensive medication slightly reduced these sialorrhea scores (r=-.25). Discussion and Conclusions: About a half of the patients reported mild to severe nocturnal hypersalivation, but its intensity seems unrelated to the clozapine dose or to its nighttime administration. No gender or age differences in hypersalivation were found. Concurrent use of other antipsychotics could lightly intensify the sialorrhea.