Twenty-five published cases of ashwagandha-associated liver injury now exist across thirteen peer-reviewed papers. Most recovered fully within weeks to months of stopping. Three did not, and all three were people with pre-existing cirrhosis who decompensated. That distribution is the whole safety message: for most healthy adults this is a rare, idiosyncratic and reversible reaction, and for a specific group it has been fatal.
A 2026 scoping review of the global literature identified 13 publications covering 25 patients with ashwagandha-attributed liver injury. The pattern is consistent: onset after weeks of use, cholestatic or mixed biochemistry, jaundice and itching rather than pain, and recovery over weeks to months after stopping. The earlier Icelandic and US case series of five patients recorded a latency of 2–12 weeks, prolonged pruritus and hyperbilirubinaemia lasting 5–20 weeks, and normalisation of liver tests within 1–5 months in four of five. Severe outcomes were concentrated: one acute liver failure requiring transplantation, and three deaths in patients with pre-existing cirrhosis. Separately, thyroid effects are documented in both directions, including thyrotoxicosis case reports and measurable T4 increases in a controlled study.
Ashwagandha is one of the better-evidenced supplements for stress, and it is also the one with the clearest signal of a specific, reproducible harm. Both statements are true and neither cancels the other.
What the Liver Injury Actually Looks Like
Not like the liver damage most people picture. Björnsson's 2020 case series from Iceland and the US Drug-Induced Liver Injury Network describes five patients, mean age 43, three male.
All five developed jaundice, with nausea, lethargy, itching and abdominal discomfort, after a latency of two to twelve weeks. The biochemical pattern was cholestatic or mixed — R ratios of 1.4 to 3.3 — rather than the hepatocellular pattern typical of paracetamol overdose. Itching and raised bilirubin persisted for five to twenty weeks.
None developed hepatic failure. Liver tests normalised within one to five months in four patients; the fifth was lost to follow-up. The one biopsy performed showed acute cholestatic hepatitis. Chemical analysis confirmed ashwagandha in the available supplements and identified no other toxic compounds.
That latency of weeks is the practical trap. A reaction that appears two months after starting a daily capsule is rarely attributed to the capsule.
What the 2026 Review Added
Scale and severity. McIntyre's team searched the peer-reviewed literature through December 2025 and found 13 qualifying publications covering 25 patients across multiple regions.
The clinical picture held: liver injury developing after weeks of use, cholestatic or mixed phenotypes predominating with jaundice and pruritus, purely hepatocellular injury less common. Where formal causality assessment was applied, ashwagandha was generally classified as a probable or likely cause. Most patients recovered after stopping.
The exceptions matter more than the average. One case of acute liver failure required transplantation. Three deaths occurred — all among patients with pre-existing cirrhosis who decompensated.
The authors' conclusion is specific and worth quoting in substance: patients with advanced chronic liver disease should be counselled to avoid ashwagandha, and herbal supplement exposure should be routinely assessed in unexplained hepatitis or cholestasis.
The Test That Would Miss It
Consumer health writing usually tells people to watch ALT, the enzyme that rises in hepatocellular injury. Ashwagandha's documented phenotype is cholestatic or mixed, which means alkaline phosphatase and bilirubin carry the signal while ALT may be the least abnormal figure on the panel.
The symptoms follow the biochemistry rather than intuition: yellowing of the eyes or skin, dark urine, pale stools, and itching without a rash. Pain is typically absent. Fatigue and nausea are non-specific enough to be blamed on anything.
If those appear, the action is to stop the supplement and get liver function tested, naming ashwagandha explicitly — supplement exposure is routinely missed in the history.
The Thyroid Signal
Separate from the liver, well documented, and running in both directions.
Gannon's 2014 analysis measured thyroid indices as a safety endpoint inside an eight-week randomised trial. All three ashwagandha-treated patients with measurable changes showed T4 increases from baseline — 7%, 12% and 24% — while six of seven placebo patients showed T4 decreases of 4% to 23%. The numbers are small and the authors are careful about that, but the direction is consistent.
Case reports go further: thyrotoxicosis following ashwagandha use has been published since 2005, including a case presenting with supraventricular tachycardia, and a case of painless thyroiditis.
The practical consequence is that ashwagandha is not thyroid-neutral. For anyone on levothyroxine, with a known thyroid condition, or stacking it alongside an iodine-bearing product such as sea moss — see our sea moss and iodine article — that is a conversation to have before starting, not after.
Who Should Avoid It
| Group | Reason | Strength |
|---|---|---|
| Cirrhosis or advanced liver disease | All three published deaths occurred in this group | Avoid — explicit review recommendation |
| Any active liver condition | Cholestatic injury on an already compromised organ | Avoid without hepatology advice |
| Existing thyroid disease or levothyroxine | Documented T4 rises and thyrotoxicosis cases | Discuss first; monitor |
| Pregnancy | Traditional abortifacient use; no safety data | Avoid |
| Autoimmune conditions | Immunomodulatory activity | Discuss first |
| On sedatives or alcohol | Additive sedation | Caution |
| Before surgery | Sedative and thyroid effects; general herbal guidance | Stop two weeks before |
Why "Natural and Ancient" Does Not Help Here
Ashwagandha has centuries of Ayurvedic use behind it, and that history is real. What it does not provide is a safety signal for the product people are actually buying.
Traditional preparation is root decoction or powder in food quantities. Modern products are standardised root extracts concentrated on withanolide content, taken daily at fixed doses for months. The case series involved supplements, not decoctions, and chemical analysis confirmed ashwagandha rather than an adulterant in the Icelandic and US cases.
Idiosyncratic drug-induced liver injury is also, by definition, not dose-predictable. It is an unpredictable reaction in a susceptible individual, which is why "I took the recommended amount" offers no protection and why a lower dose is not a solution.
Common, Mild and Expected
Most people who stop ashwagandha do so for something far more ordinary. Gastrointestinal upset, nausea and loose stools are the commonest complaints, particularly on an empty stomach. Drowsiness is frequent — it is often why people take it in the evening rather than a problem. Headache appears in trial adverse-event tables.
Those are the expected costs of taking it, and our dosage guide covers how timing and food change them. They are not the reason this article exists.
What to Do
- Do not take it if you have cirrhosis or advanced liver disease. This is the one categorical exclusion, and it is where every published death occurred.
- Know the symptom set: jaundice, dark urine, pale stools, itching. Pain is usually absent, so its absence is not reassurance.
- Expect a latency of weeks. Onset two months in is typical, which is exactly when people stop suspecting the supplement.
- If you get liver tests, ask for bilirubin and ALP, not just ALT. The documented pattern is cholestatic or mixed.
- Name it in your medication history. Herbal exposure is routinely missed in unexplained hepatitis or cholestasis.
- Take thyroid status seriously. Measured T4 increases and thyrotoxicosis reports both exist — relevant to levothyroxine users and to anyone stacking iodine.
- Consider whether a mushroom alternative fits your goal. For stress specifically, our ashwagandha versus reishi comparison sets out what each one actually has behind it.
The Honest Summary
Twenty-five documented cases against tens of millions of doses taken worldwide is a rare event, and most of those cases resolved completely once the supplement stopped. It would be wrong to describe ashwagandha as dangerous to the general population on this evidence.
It would be equally wrong to leave out the shape of the harm. The syndrome is reproducible enough that a scoping review calls it one; it arrives weeks after starting, presents cholestatically so the obvious blood test may look least abnormal, and has killed three people — all of whom already had cirrhosis. Add a thyroid effect measurable in a controlled study and case-reported as thyrotoxicosis, and the sensible position is not avoidance but informed use: know the exclusions, know the symptoms, and tell a clinician you are taking it.
Frequently Asked Questions
Can ashwagandha damage your liver?
Rarely, and idiosyncratically. Twenty-five cases across thirteen publications describe liver injury developing after weeks of use, usually cholestatic or mixed, with most patients recovering over weeks to months after stopping.
Who is most at risk?
People with pre-existing cirrhosis. All three deaths in the published literature occurred in that group through decompensation, which is why the scoping review explicitly recommends counselling patients with advanced chronic liver disease to avoid it.
What are the warning signs?
Jaundice, dark urine, pale stools and itching without a rash, usually accompanied by nausea and lethargy. Abdominal pain is typically absent, and onset is commonly two to twelve weeks after starting.
Does ashwagandha affect the thyroid?
Yes, and it is not neutral. In a controlled study all three treated patients with measurable change showed T4 increases of 7%, 12% and 24% while most placebo patients fell, and thyrotoxicosis has been reported in case literature since 2005.
Is a lower dose safer?
Not reliably. Idiosyncratic drug-induced liver injury is by definition not dose-predictable, so taking the recommended amount is not protective and reducing the dose is not a substitute for knowing the exclusions.
Shop Thoughtfully
Ashwagandha capsules (120 caps €29) are a single-ingredient standardised root extract, which matters here — several case reports involved multi-ingredient formulations where attribution was harder and a second hepatotoxic agent could not be excluded. If liver disease rules ashwagandha out for you, Reishi capsules (120 caps €39) address the fatigue and stress endpoint through different chemistry. Free shipping on orders over €50.
Related Articles
- Ashwagandha Dosage Guide
- Ashwagandha Benefits: What the Research Shows
- Ashwagandha vs Reishi for Stress
- Sea Moss and Iodine
- Mushroom Supplements Before Surgery
- Mushroom Supplements and Medication Interactions
- Liver Recovery After Alcohol Damage
Sources
- McIntyre D, Nguyen P, Kim Y, Meyer B, Salloum M. Ashwagandha (Withania somnifera)-associated liver injury: a scoping review of clinical characteristics and safety considerations. Cureus. 2026;18(5):e109764. PubMed 42367407
- Björnsson HK, Björnsson ES, Avula B, et al. Ashwagandha-induced liver injury: a case series from Iceland and the US Drug-Induced Liver Injury Network. Liver Int. 2020;40(4):825-829. PubMed 31991029
- Gannon JM, Forrest PE, Roy Chengappa KN. Subtle changes in thyroid indices during a placebo-controlled study of an extract of Withania somnifera in persons with bipolar disorder. J Ayurveda Integr Med. 2014;5(4):241-245. PubMed 25624699
- Kamal HI, Patel K, Brdak A, Heffernan J, Ahmad N. Ashwagandha as a unique cause of thyrotoxicosis presenting with supraventricular tachycardia. Cureus. 2022;14(3):e23494. PubMed 35475098
- van der Hooft CS, Hoekstra A, Winter A, de Smet PA, Stricker BH. [Thyrotoxicosis following the use of ashwagandha]. Ned Tijdschr Geneeskd. 2005;149(47):2637-2638. PubMed 16355578
- Coope OC, Willems MET, Levington A, Tallon MJ, Roman-Viñas B, Spurr TJ. Back to the roots: safety and tolerability of standardised ashwagandha (Withania somnifera) root extract in healthy adults — a systematic review of biomarkers and adverse events. Pharmaceuticals (Basel). 2026;19(5):725. PubMed 42198398