Evidence-backed FAQ
What are the safety cautions for ashwagandha?
Ashwagandha can cause drowsiness and gastrointestinal symptoms, and rare reports have linked supplements to liver injury. Short-term tolerability observations do not establish safety for everyone or for long-term use.[1]
Important limitations
Rare reports have linked ashwagandha supplements with liver injury. Short-term tolerability findings do not rule out rare harms or establish long-term safety.[1]
What the evidence shows
NIH guidance describes short-term tolerability observations for ashwagandha over about three months, while safety over longer periods remains unknown. Short studies cannot establish safety for every person, preparation, or duration of use.[1]
Pregnancy and breastfeeding
NCCIH advises avoiding ashwagandha during pregnancy and not using it while breastfeeding. Short-term studies in other adults do not establish safety during pregnancy or breastfeeding; discuss any exposure or supplement plans with a qualified healthcare professional.[1]
Conditions and planned surgery
NCCIH does not recommend ashwagandha for people with thyroid or autoimmune disorders or those who are about to have surgery. Discuss these conditions and any planned surgery with your healthcare professional before considering ashwagandha; supplement research does not justify changing prescribed care.[1]
NCCIH advises people with hormone-sensitive prostate cancer to avoid ashwagandha because it may increase testosterone. This is a condition-specific safety caution, not a treatment recommendation or an instruction to change cancer care.[1]
Medication interactions
Ashwagandha may interact with medicines for diabetes or high blood pressure, immunosuppressants, sedatives, anticonvulsants, and thyroid hormone medicines. Discuss possible interactions with your prescriber or pharmacist before use; do not stop, replace, or adjust prescribed medicines based on supplement information.[1]
Read the supporting evidence summaries
The linked research pages provide study populations, formulations, doses, outcomes, and limitations in greater detail.
Related questions
References
- Ashwagandha: Usefulness and Safety. NIH National Center for Complementary and Integrative Health. Retrieved 2026-09-30. Government health fact sheet View source →