tuneTypical Dose
NASH trials have used standardized products from 420 mg to 700 mg three times daily
Botanical
Milk Thistle
Silybum marianum
Evidence TierDWADA NOT PROHIBITED
watchEffect Window
Liver trials are long, and meaningful outcomes are slow to change.
check_circleCompliance
WADA NOT PROHIBITED
Overview
Clinical Summary
Milk thistle is widely used for liver support, but controlled trials do not show dependable disease-modifying benefit in chronic liver disease or NASH.
Milk thistle is one of the most popular liver supplements, yet its clinical evidence is weaker than its reputation. Systematic reviews and randomized trials generally show that silymarin is safe and may slightly change some lab markers, but it has not shown convincing benefit on major liver outcomes. A newer poison-center study suggests tolerability and a possible kidney-protection signal in acute mushroom poisoning, but that does not rescue the negative chronic-liver record. Milk thistle remains a low-confidence adjunct, not a proven liver therapy.
Silymarin is usually framed as antioxidant and hepatoprotective, but clinical translation into strong liver outcomes has been inconsistent.
Outcomes
What This Is Expected To Influence
Primary Outcomes
- No dependable disease-modifying benefit established in chronic liver disease
Secondary Outcomes
- Possible small changes in liver enzymes with uncertain clinical relevance
Safety
Contraindications and Interactions
Contraindications
No entries provided
Side effects
- GI upset
Interactions
- Drugs heavily reliant on hepatic metabolism
Avoid if
- You are delaying evidence-based evaluation of persistent liver disease
Evidence
Study-level References
mil-SRC-001Systematic review and meta-analysis
Sourceopen_in_newRambaldi A, et al. Milk thistle for the treatment of liver disease: a systematic review and meta-analysis. Am J Med. 2002. doi:10.1016/S0002-9343(02)01444-5. PMID:12427501.
Population: Adults with chronic liver disease from randomized placebo-controlled milk-thistle trials.
Dose protocol: Multiple standardized milk-thistle regimens across chronic liver disease trials
Key findings: No convincing mortality, histology, or major biochemical benefit.
Notes: Best broad review.
Paper content
This review remains useful because it makes the central point clearly. Milk thistle appears safe, but it does not show convincing benefit on major liver outcomes.
mil-SRC-002Randomized controlled trial
Sourceopen_in_newNavarro VJ, et al. Silymarin in non-cirrhotics with non-alcoholic steatohepatitis: A randomized, double-blind, placebo controlled trial. Clin Gastroenterol Hepatol. 2019. doi:10.1016/j.cgh.2019.08.051. PMID:31536511.
Population: Adults with non-cirrhotic NASH.
Dose protocol: Legalon 420 mg or 700 mg three times daily for 48 to 50 weeks
Key findings: No significant primary-endpoint benefit in non-cirrhotic NASH.
Notes: Best modern direct trial.
Paper content
This is the best modern direct milk-thistle trial for NASH and it was negative on its primary endpoint. That keeps confidence low despite the supplement's popularity.
mil-SRC-003Retrospective observational study (poison center data analysis).
Sourceopen_in_newTangsuwanaruk T, Tansuwannarat P, Tongpoo A, Mirin K, Trakulsrichai S. Effect of oral silymarin in patients with acute hepatotoxic mushroom poisoning: an analysis of poison center data. Clin Toxicol (Phila). 2026;64(2):112-122. doi:10.1080/15563650.2025.2586098. PMID:41378447.
Population: Adults and children presenting with acute hepatotoxic mushroom poisoning.
Dose protocol: Oral silymarin in acute hepatotoxic mushroom poisoning (dose not standardized)
Key findings: No mortality benefit after adjustment. Reduced acute kidney injury (adjusted risk difference -13.9%). No adverse drug reactions.
Notes: Largest real-world silymarin safety dataset in acute poisoning. Observational design limits causal claims.
Paper content
This retrospective analysis of Thai poison center data examined outcomes in 255 patients with hepatotoxic mushroom poisoning, comparing those who received oral silymarin (n=33) to those who did not. Silymarin was not associated with reduced mortality after adjusting for confounders, but it was associated with a meaningful reduction in acute kidney injury (adjusted risk difference -13.9%). No reduction in acute liver failure or hospital length of stay was observed. No adverse drug reactions from silymarin were reported. The study adds a large real-world safety signal for silymarin in acute poisoning but does not establish a mortality benefit. Its observational design and small silymarin subgroup limit causal inference.