Background: Anxiety disorders are the most universal psychiatric problems in the general
population. Due to their chronic nature, these diseases are managed with a multi-drug regimen lasting for
a long period of time. Medication discontinuation leads to 25% and 80% recurrence in the first month and
the first year, respectively. Despite several treatment approaches, there is no specific and optimal method
for patient management. Therefore, it is necessary to find some new theraputic approaches with fewer
side effects. Withania somnifera is a plant with GABAergic property responsible for its anxiolytic effect.
The aim of this study was to investigate the effect of W. somnifera root extract as an alternative therapy to
reduce standard generalized anxiety disorder (GAD) symptoms.
Methods: Forty patients who met the inclusion criteria (with a confirmed diagnosis of GAD as stated in
the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR)
took part in this randomized double-blind placebo-controlled trial and were randomly selected for
participation in the treatment group (W. somnifera extract, 1g/day; n = 22) or the placebo group (n = 18).
All patients were under treatment with Selective Serotonin Reuptake Inhibitors (SSRIs) and were
prescribed one capsule of the extract or placebo per day for six weeks. The Hamilton anxiety rating scale
(HAM-A) was used to assess the severity of GAD symptoms at baseline as well as the second and sixth
weeks of the trial.
Results: Comparison of the HAM-A scores during the course of the trial revealed a significant
amelioration ofHAM-A score in the treatment group versus placebo (14 and 8 units reduction,
respectively (P < 0.05)). Moreover, there was a significant difference in the reduction of GAD score
between the second (P =0.04) and sixth week (P =0.02) in the treatment group. The extract was safe and
no adverse effect was observed during the trial.
Conclusion: W. somnifera extract offers some potential advantages as a safe and effective adjunctive
therapy to SSRIs in GAD.