Safety and tolerability of Ashwagandha (Withania somnifera) root extract in healthy adults: a prospective, non-comparative study

Background and aim Ashwagandha, adaptogenic herb traditionally used to enhance resilience to stress and promote overall well-being. Although its safety at conventional doses is well established, evidence regarding the safety of higher doses in healthy adults remains limited. The present study aimed to evaluate the safety and tolerability of Ashwagandha root extract (ARE) administered at a dose of 2000 mg/day in healthy adults over 12 weeks. Methods This was a prospective, single-arm, non-comparative clinical study conducted in healthy adults aged 18–65 years. Participants received ARE 500 mg capsules (total daily dose of 2000 mg) orally for 12 weeks. Primary safety outcomes included laboratory evaluations of renal, hepatic, and thyroid parameters. Secondary safety outcomes included clinical assessment of adverse events and changes in quality of life assessed using the SF-36 questionnaire. Results Over 12 weeks, minor changes ( p < 0.05) occurred in serum bilirubin, alkaline phosphatase, creatinine, transaminases, blood urea, and thyroid parameters in PP dataset ( n = 124) who completed study. All values remained within reference ranges and were clinically insignificant, with most values slightly reduced except a small increase in alkaline phosphatase. No serious or clinically significant changes were noted. In ITT dataset ( n = 145) most participants (85.5%) experienced no adverse events, with mild nausea being the most common at 5.5%. Quality of life (SF-36 scores) demonstrated improvement ( p < 0.05) after 12 weeks in the SF-36 domains of physical functioning, role limitations due to physical health, social functioning, and pain. Conclusion High-dose Ashwagandha root extract (2000 mg/day) was well tolerated and demonstrated a favourable safety profile in healthy adults over 12 weeks. Trial registration https://ctri.nic.in/Clinicaltrials/pmaindet2.php?EncHid=ODE3NTk=&Enc=&userName= , Identifier (CTRI/2023/04/051607).