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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 ?
After commencing radiotherapy and the studied interventions, the NCICTC and WHO oral mucositis scores were significantly lower in the silymarin group in weekly evaluations compared to the placebo group.
Attenuation of UVA-induced damage to human keratinocytes by silymarin.
Because silymarin can be used as a natural antioxidant agent, the aim of this work was to study the ameliorative effect of silymarin on radiation-induced liver injury in rats.
Effect of silymarin plus vitamin E in patients with non alcoholic fatty liver disease.
Uthayashanker Ezekiel Dr Ezekiel said: "Concentrations of curcumin and silymarin that are too high could be harmful to people.
Anti-inflammatory activity of silymarin in patients with knee osteoarthritis.
A double-blinded randomized controlled trial of silymarin for the prevention of antituberculosis drug-induced liver injury.
Keeping in view the importance of milk thistle for production of flavonoids of the silymarin group, the cultivation and production of this medicinal plant is essential for the pharmaceutical industries.
Treatment with AEBS 250, 500 mg/kg and, the Silymarin 100 mg/kg showed a significant (P<0.
surattensis seed extract or silymarin pretreatment significantly elevated the previously dropped levels of GSH and SOD which led to depletion of the MDA levels in liver tissue.