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 therapeutic 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. The clinical trial protocol has been registered under the Iranian Registry
of Clinical Trials (IRCT20180615040105N1).