Effect of Ashwagandha as Adjunct Therapy on BDNF and Cognitive Function in Schizophrenia Patients

Overview

This study aims to evaluate the effectiveness of Ashwagandha (Withania somnifera) as an adjunctive therapy in improving serum brain-derived neurotrophic factor (BDNF) levels and cognitive function in patients with schizophrenia receiving risperidone treatment. This study uses a controlled clinical trial design involving two groups: a control group receiving risperidone only and an intervention group receiving risperidone combined with Ashwagandha extract. Cognitive function is assessed using the Montreal Cognitive Assessment Indonesian version (MoCA-Ina), and serum BDNF levels are measured at baseline and after 8 weeks of treatment. The study also aims to compare changes in cognitive function and BDNF levels between the two groups and to analyze the correlation between cognitive improvement and changes in BDNF levels. The findings are expected to provide evidence regarding the potential role of Ashwagandha as an adjunctive therapy for cognitive impairment in schizophrenia.

This randomized controlled trial was conducted at Dadi Psychiatric Hospital (RSKD Dadi), South Sulawesi Province, Makassar, Indonesia, in 2026. BACKGROUND: Schizophrenia is a chronic psychiatric disorder characterized by cognitive impairment and neurobiological alterations, including decreased levels of brain-derived neurotrophic factor (BDNF), which plays a key role in neuroplasticity and cognitive function. Standard treatment with antipsychotics such as risperidone improves psychotic symptoms but has limited effects on cognitive deficits. Ashwagandha (Withania somnifera), a medicinal plant with neuroprotective, anti-inflammatory, and antioxidant properties, has been proposed as an adjunctive therapy to improve cognitive function and increase BDNF levels. However, evidence regarding its effectiveness in schizophrenia remains limited. INTERVENTION: The intervention group received risperidone in standard therapeutic doses combined with Ashwagandha extract for 8 weeks. The control group received risperidone monotherapy for the same duration. Both groups continued standard clinical care throughout the study period. RANDOMIZATION AND BLINDING: Participants were allocated into two groups (intervention and control). Randomization was performed using the Sequentially Numbered Opaque Sealed Envelope (SNOSE) method, prepared by a separate research assistant and disclosed only after informed consent and baseline assessments were completed. The study employed a double-blind design in which both participants and outcome assessors were blinded to group allocation. OUTCOME MEASURES: The primary outcomes were: (1) change in cognitive function assessed using the Montreal Cognitive Assessment Indonesian version (MoCA-Ina) from baseline to Week 8; and (2) change in serum BDNF levels from baseline to Week 8. Secondary analysis included comparison of changes between groups and evaluation of the correlation between changes in MoCA-Ina scores and serum BDNF levels. ETHICAL APPROVAL: This study was approved by the Health Research Ethics Committee, Faculty of Medicine, Hasanuddin University, and conducted in accordance with the Declaration of Helsinki. All participants provided written informed consent prior to enrollment.