Ashwagandha (Withania somnifera)

Evidence-based guide to Ashwagandha: benefits, dosage, safety and interactions.

Evidence

Moderate: 2015 RCT (n=50, KSM-66) showed significant improvement across all six FSFI domains for stress-related sexual dysfunction.

Traditional use and mechanism

Primary male rasayana in Ayurvedic medicine (female also). Adaptogen and anti-stress tonic; sexual dysfunction associated with chronic stress; sleep support. Sanskrit: 'smell of horse' (strength and virility). Used in Ayurveda for ≥3,000 years.

Safety

Well-tolerated in clinical trials at standard doses. Most common side effects: mild GI upset, loose stools at high doses. Thyroid stimulation is the primary safety concern — relevant for patients on thyroid medication or with thyroid disease. 2015 Dongre et al. RCT (n=50): no serious adverse events at 300 mg twice daily (KSM-66) for 8 weeks.