Adjunctive Use of a Standardized Extract of Withania somnifera (Ashwagandha) to Treat Symptom Exacerbation in Schizophrenia

OBJECTIVE: To determine if adjunctive treatment with a standardized extract of Withania somnifera (WSE), with known anti-inflammatory and immunomodulating properties, improves psychopathology and stress in patients with schizophrenia or schizoaffective disorder (DSM-IV-TR). METHODS: Patients experiencing an exacerbation of symptoms were assigned to WSE (1,000 mg/d) or placebo for 12 weeks, added to their antipsychotic medication, in a random-assignment, double-blind, placebo-controlled study conducted from April 2013 to July 2016. Primary outcomes were change from baseline to end of treatment on the Positive and Negative Syndrome Scale (PANSS total, positive, negative, and general symptoms) between treatment groups. Secondary outcomes evaluated stress and inflammatory indices using the Perceived Stress Scale (PSS), S100 calcium-binding protein B (S100B), and C-reactive protein (CRP). RESULTS: Sixty-six randomized patients (n = 33 per group) provided efficacy data. Beginning at 4 weeks and continuing to the end of treatment, WSE produced significantly greater reductions in PANSS negative, general, and total symptoms (Cohen d: 0.83, 0.76, 0.83), but not positive symptoms, when compared to placebo. PSS scores improved significantly with WSE treatment compared to placebo (Cohen d: 0.58). CRP and S100B declined more in the WSE group but were not significantly different from placebo. Adverse events were mild to moderate and transient; somnolence, epigastric discomfort, and loose stools were more common with WSE. No significant between-treatment differences were noted in body weight, vital signs, or laboratory measures, which remained stable. CONCLUSIONS: This early study suggests that adjunctive treatment with a standardized extract of Withania somnifera provides significant benefits, with minimal side effects, for negative, general, and total symptoms and stress in patients with recent exacerbation of schizophrenia. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01793935.