Nutritional Supplement

Milk Thistle

Side Effects

Milk thistle extract has almost no known side effects and may be used by most people, including pregnant and breast-feeding women. In fact, it has been recommended as a treatment for itching due to poor gallbladder function during pregnancy.23 Since silymarin stimulates liver and gallbladder activity, it may have a mild, transient laxative effect in some people. This will usually cease within two to three days.

There is one case report of a 57-year-old Australian woman experiencing several episodes of nausea, abdominal pain, vomiting and weakness after taking a milk thistle preparation.24 This case is so atypical, however, that the Adverse Drug Reactions Advisory Committee of Australia questioned whether the product taken might not have contained other herbs or additives that could be responsible for the adverse reaction. In addition, rare but serious allergic reactions to milk thistle have been reported.

References

1. Wagner H, Horhammer L, Munster R. The chemistry of silymarin (silybin), the active principle of the fruits of Silybum marianum (L.) Gaertn. Arzneim-Forsch Drug Res 1968;18:688-96.

2. Hikino H, Kiso Y, Wagner H, Fiebig M. Antihepatotoxic actions of flavonolignans from Silybum marianum fruits. Planta Medica 1984;50:248-50.

3. Faulstich H, Jahn W, Wieland T. Silibinin inhibition of amatoxin uptake in the perfused rat liver. Arzneimittelforschung 1980;30:452-4.

4. Tuchweber B, Sieck R, Trost W. Prevention by silibinin of phalloidin induced hepatotoxicity. Toxicol Appl Pharmacol 1979;51:265-75.

5. Feher J, Lang I, Deak G, et al. Free radicals in tissue damage in liver diseases and therapeutic approach. Tokai J Exp Clin Med 1986;11:121-34.

6. Sonnenbichler J, Zetl I. Stimulating influence of a flavonolignan derivative on proliferation, RNA synthesis and protein synthesis in liver cells. In Assessment and Management of Hepatobiliary Disease, ed. L Okolicsanyi, G Csomos, G Crepaldi. Berlin: Springer-Verlag, 1987, 265-72.

7. Schuppan D, Strösser W, Burkard G, Walosek G. Legalon® lessens fibrosing activity in patients with chronic liver diseases. Zeits Allgemeinmed 1998;74:577-84.

8. Salmi HA, Sarna S. Effect of silymarin on chemical, functional and morphological alterations of the liver. A double-blind controlled study. Scand J Gastroenterol 1982;17:517-21.

9. Leng-Peschlow E. Alcohol-related liver diseases-use of Legalon®. Z Klin Med 1994;2:22-7.

10. Ferenci P, Dragosics B, Dittrich H, et al. Randomized controlled trial of silymarin treatment in patients with cirrhosis of the liver. J Hepatol 1989;9:105-13.

11. Velussi M, Cernogoi AM, De Monte A, et al. Long-term (12 months) treatment with an antioxidant drug (silymarin) is effective on hyperinsulinemia, exogenous insulin need and malondialdehyde levels in cirrhotic diabetic patients. J Hepatology 1997;26:871-9.

12. Parés A, Planas R, Torres M, et al. Effects of silymarin in alcoholic patients with cirrhosis of the liver: results of a controlled, double-blind, randomized and multicenter trial. J Hepatol 1998;28:615-21.

13. Nassuato G, Iemmolo RM, et al. Effect of silibinin on biliary lipid composition. Experimental and clinical study. J Hepatol 1991;12:290-5.

14. Palasciano G, Portinascasa P, Palmieri V, et al. The effect of silymarin on plasma levels of malondialdehyde in patients receiving long-term treatment with psychotropic drugs. Curr Ther Res 1994;S5:S37-45.

15. Allain H, Schück S, Lebreton S, et al. Aminotransferase levels and silymarin in de novo tacrine-treated patients with Alzheimer's disease. Dementia Geriatr Cogn Disorders 1999;10:181-5.

16. Ebrahimpour-Koujan S, Gargari B, Mobasseri M, et al. Lower glycemic indices and lipid profile among type 2 diabetes mellitus patients who received novel dose of Silybum marianum (L.) Gaertn. (silymarin) extract supplement: A Triple-blinded randomized controlled clinical trial. Phytomedicine 2018;44:39–44.

17. Ebrahimpour Koujan S, Gargari B, Mobasseri M, et al. Effects of Silybum marianum (L.) Gaertn. (silymarin) extract supplementation on antioxidant status and hs-CRP in patients with type 2 diabetes mellitus: a randomized, triple-blind, placebo-controlled clinical trial. Phytomedicine 2015;22:290–6.

18. Huseini H, Larijani B, Heshmat R, et al. The efficacy of Silybum marianum (L.) Gaertn. (silymarin) in the treatment of type II diabetes: a randomized, double-blind, placebo-controlled, clinical trial. Phytother Res 2006;20:1036–9.

19. Di Pierro F, Bellone I, Rapacioli G, Putignano P. Clinical role of a fixed combination of standardized Berberis aristata and Silybum marianum extracts in diabetic and hypercholesterolemic patients intolerant to statins. Diabetes Metab Syndr Obes 2015;8:89–96.

20. Di Pierro F, Putignano P, Villanova N, et al. Preliminary study about the possible glycemic clinical advantage in using a fixed combination of Berberis aristata and Silybum marianum standardized extracts versus only Berberis aristata in patients with type 2 diabetes. Clin Pharmacol 2013;5:167–74.

21. Nassuato G, Iemmolo RM, et al. Effect of silibinin on biliary lipid composition. Experimental and clinical study. J Hepatol 1991;12:290-5.

22. Brown DJ. Herbal Prescriptions for Better Health. Rocklin, CA: Prima Publishing, 1996, 151-8.

23. Reyes H. The spectrum of liver and gastrointestinal disease seen in cholestasis of pregnancy. Gastroert Clin N Am 1992;21:905-21.

24. Adverse Drug Reactions Advisory Committee. An adverse reaction to the herbal medication milk thistle (Silybum marianum). MJA 1999;170:218-9.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.