Dose effect of buspirone combined with clozapine on cognitive function in patients with schizophrenia

Br J Clin Pharmacol. 2026 Apr 16. doi: 10.1002/bcp.70549. Online ahead of print.

Abstract

Aim: This study aimed to evaluate the augmentation effects of different doses of buspirone on psychiatric symptoms and cognitive function in patients with schizophrenia.

Methods: A prospective study design was employed, enrolling 46 patients with schizophrenia treated at the Fourth People's Hospital of Wuhu. Patients were randomly assigned to three groups: a control group, experimental group 1 (5 mg of buspirone) or experimental group 2 (10 mg of buspirone). The control group received clozapine monotherapy, whereas the experimental groups received adjunctive buspirone at different doses alongside clozapine. The Positive and Negative Syndrome Scale (PANSS) and the Chinese version of the Repeatable Battery for the Assessment of Neuropsychological Status were used to assess psychiatric symptoms and cognitive function. A linear mixed-effects model was employed for statistical analysis.

Results: After 4 weeks of treatment, both experimental groups showed greater reductions in total PANSS scores than the control group (d = 0.68 and 0.82, respectively), with improvements in positive and negative symptoms being particularly pronounced in experimental group 2 (d = 0.68 and 0.85, respectively). By week 8, general symptoms had improved significantly in both experimental groups. < u > A significant group × time interaction was observed (partial η2 = 0.15)</u>, indicating that experimental group 2 exhibited more rapid improvement than experimental group 1. With respect to cognitive function, the experimental groups demonstrated significant improvements in immediate memory (d > 0.5) and visuospatial/constructional abilities (d > 0.45) at week 8, with additional improvements in language abilities (d > 0.5) by week 12.

Conclusions: Buspirone is effective in alleviating psychiatric symptoms and cognitive deficits in patients with schizophrenia, thereby enhancing clinical outcomes.

Keywords: buspirone; clozapine; cognitive impairment; schizophrenia.