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milk thistle

(milk this-ul) ,

Holy thistle

(trade name),

Lady's thistle

(trade name),

Mary Thistle

(trade name),


(trade name),


(trade name)


Therapeutic: antidotes
Cirrhosis, chronic hepatitis, gallstones, psoriasis, liver cleansing and detoxification, treatment of liver toxicity due to Amanita mushroom poisoning (European IV formulation) and chemicalsDyspepsia (in combination with other herbs)Diabetes


The active component, silymarin, has antioxidant and hepatoprotectant actions. Silymarin helps prevent toxin penetration and stimulates hepatocyte regeneration.

Therapeutic effects

Liver detoxification.
Improved dyspepsia symptoms.
Decreased fasting blood glucose.


Absorption: 23–47% absorbed after oral administration.
Distribution: Unknown.
Metabolism and Excretion: Hepatic metabolism by cytochrome P450 3A4.
Half-life: 6 hr.

Time/action profile

PO5–30 days or moreunknownunknown


Contraindicated in: Pregnancy and lactation (insufficient information available); Allergy to chamomile, ragweed, asters, chrysanthemums and other members of the family Asteraceae/Compositae.
Use Cautiously in: Hormone sensitive cancers/conditions (milk thistle plant parts may have estrogenic effects).

Adverse Reactions/Side Effects


  • Laxative effect
  • nausea
  • bloating
  • anorexia


  • Allergic reactions


In vitro, milk thistle extract inhibited the drug-metabolizing enzyme cytochrome P450 3A4. Interactions have not been reported in humans, but milk thistle should be used cautiously with other drugs metabolized by 3A4, such as cyclosporine, carbamazepine, HMG-CoA inhibitors, ketoconazole, and alprazolam.None known.
Oral (Adults) Hepatic cirrhosis—420 mg/day of extract containing 70–80% silymarin; Chronic active hepatitis—240 mg bid of silibinin; Diabetes—200 mg tid of silymarinTea—3–4 times daily 30 minutes before meals. Tea is not recommended as silymarin is not sufficiently water soluble.
Intravenous (Adults) 20–50 mg/kg over 24 hr, 48 hr post mushroom ingestion (IV formulation not available in US).


Capsules: OTC
Tablets: OTC
Crude drug: OTC
Tea: OTC
Extract: OTC

Nursing implications

Nursing assessment

  • Assess patients for signs of liver failure (jaundice, mental status changes, abdominal distention, ascites, generalized edema).
  • Evaluate consistency and frequency of bowel movements.
  • Lab Test Considerations: Monitor liver function, lipid profile, and blood glucose periodically during therapy.

Potential Nursing Diagnoses

Deficient knowledge, related to medication regimen (Patient/Family Teaching)


  • Orally as an extract, capsule, tablets or as a dried fruit as a single daily dose or divided into three doses.
  • Tea is not recommended as milk thistle is not water-soluble.

Patient/Family Teaching

  • Inform patient of the symptoms of liver failure; advise patient to report worsening symptomotolgy promptly to healthcare professional.
  • Emphasize the need for blood tests to monitor liver function tests.
  • Advise patients to avoid alcohol and follow diet for liver or gall bladder disease being treated.

Evaluation/Desired Outcomes

  • Normalization of liver function tests.
  • Reduction in jaundice, abdominal distention, fatigue and other symptoms associated with liver disease.


Herbal medicine
An extract of milk thistle (Silybum marianum) seeds, which has been used for hepatitis and cirrhosis, the major constituent of which is silibinins A and B.

silymarin (sil·ē·märˑ·n),

n a type of flavonoid compound found in milk thistle. Extracts are used to protect the liver from environmental toxins.
References in periodicals archive ?
Conclusion: Our data suggested that glycyrrhizin, silymarin, and ursodeoxycholic acid regulated the expression of genes relevant to apoptosis and oxidative stress in HepG2 cells.
The primary findings of the study support that consuming 140mg supplementation of silymarin, three times daily over 45 days modulates oxidative stress and inflammatory biomarkers, with observations of significantly enhanced SOD and GPX levels and decreased hs-CRP concentrations, with authors concluding that silymarin may be beneficial in the management of diabetes complications.
OVX III) Oral administration of silymarin (SIL; 50 mg/kg/day) and Calcium (250mg /kg body weight/day) from fifth postoperative day for 60 days.
Silymarin that is available in tablet form may be quite variable in bio-available flavolignans.
Comparative effects of silymarin and vitamin E supplementation on oxidative stress markers, and hemoglobin levels among patients on hemodialysis.
27) The authors concluded that silymarin posed a low effect on CYP3A4 and had little risk of interfering with the pharmacokinetic activity of Irinotecan.
d) Silymarin may have direct activity on nitric oxide synthase and thus reduce free radical formation.
Silymarin is difficult to absorb, however, and some studies have apparently indicated that a silymarin complex works better than silymarin on its own.
A randomised, double-blind pilot trial was conducted to assess the effects of a combination of selenium and silymarin in men with LUTS, BPH and prostate specific antigen (PSA) <2.
Ninety-six patients (aged 28-55 years) with melasma (disease duration, 2-6 years) were randomly assigned to apply, in double-blind fashion, silymarin cream (7 mg or 14 mg of silymarin per ml) or placebo cream to the affected areas twice a day for 4 weeks.