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

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.

Inclusion criteria

• Male patients diagnosed with schizophrenia based on ICD-10/PPDGJ III criteria
• Aged 20-45 years
• Duration of illness ≤ 5 years
• Patients who have passed the acute phase (PANSS-EC < 15)
• Receiving risperidone 4 mg/day
• Willing to participate and provide written informed consent

Exclusion criteria

• Presence of organic comorbid diseases
• History of substance abuse (NAPZA) within the last 1 year, except caffeine and nicotine
• Use of anti-inflammatory drugs, antibiotics, or antioxidant agents
• Intellectual disability (mental retardation)