Is Ashwagandha Safe? Interactions and Cautions
Cases of liver injury associated with ashwagandha have been reported and reviewed in the medical literature, and some regulators have acted on safety reviews. It is not recommended in pregnancy and may interact with thyroid, sedative, immunosuppressant and diabetes medication. Speak to a pharmacist before starting if you take any prescription.
Ashwagandha is widely sold and widely used, and it also carries more substantive safety considerations than most botanicals in this catalogue. This page sets out what has been reported and where medical advice is not optional.
Liver injury reports
Cases of liver injury associated with ashwagandha products have been reported and reviewed in the medical literature. The NIH LiverTox database maintains an entry on ashwagandha summarising the published case reports, and regulators in some countries have acted on the basis of safety reviews — Denmark has restricted sale.
These are reported associations rather than a demonstrated rate, and they concern products whose composition is often not fully characterised. The practical takeaway is not panic but attention: symptoms suggesting liver problems — yellowing of the skin or eyes, dark urine, persistent nausea, pain in the upper right abdomen, unusual fatigue — warrant stopping the product and contacting a doctor promptly.
Who should not take it without medical advice
- Pregnancy — ashwagandha is not recommended in pregnancy.
- Breastfeeding — there is insufficient information to consider it established as safe.
- Thyroid conditions or thyroid medication — ashwagandha may affect thyroid hormone levels, which matters both for people with thyroid disease and for anyone whose medication is titrated to a level.
- Autoimmune conditions — discuss with the clinician managing the condition.
- Existing liver disease, or medications known to affect the liver.
- Before surgery — tell your anaesthetist about any supplement you take.
- Children — not without paediatric advice.
Medication interactions
Reported or plausible interactions include sedatives and benzodiazepines, immunosuppressants, thyroid medication, diabetes medication and blood pressure medication. If you take any regular prescription, ask a pharmacist before starting ashwagandha. This is a short conversation and it is the right one to have.
Product variability
Botanical supplements vary in composition between manufacturers, and the preparation used in a study is not necessarily the preparation in the bottle. Products stating an extract ratio, a withanolide standardisation and a named preparation are telling you more than products stating none — see withanolides and extract ratios.
If something feels wrong
Stop the product and speak to a healthcare professional. In an emergency contact your local emergency services. Adverse reactions can be reported to the FDA through MedWatch, or in the UK through the Yellow Card scheme.
This page is consumer information, not medical advice. Please read our medical disclaimer.