milk thistle
(milk this-ul)


OTHER NAMES:
Holy thistle, Lady's thistle, Mary Thistle, Silymarin

CLASSIFICATION(S):
Therapeutic: antidotes



COMMON USES
Cirrhosis, chronic hepatitis, gallstones, psoriasis, liver cleansing and detoxification, treatment of liver toxicity due to alcohol, Amanita mushroom poisoning (European IV formulation) and chemicals.
ACTIONThe active component, silymarin, has antioxidant and hepatoprotectant actions. Silymarin helps prevent toxin penetration and stimulates hepatocyte regeneration.
Therapeutic Effects:

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


CONTRAINDICATIONS AND PRECAUTIONS
Contraindicated in:

Pregnancy and lactation (insufficient information available)
Allergy to chamomile, ragweed, asters, chrysanthemums and other members of the family Compositae.
Use Cautiously in:


ADVERSE REACTIONS AND SIDE EFFECTS*
*CAPITALS indicate life threatening; underlines indicate most frequent.

GI: Laxative effect.
Misc: Allergic reactions.
INTERACTIONS
Natural Product–Drug:

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 cyclosporin, carbamazepine, HMG-CoA inhibitors, ketoconazole, and alprazolam.
Natural Product–Natural Product:

None known.
ROUTE AND COMMONLY USED DOSES
PO (Adults): Extract (70%)—200–400 mg/d; Dried fruit/seed—12–15 g/day; Tea—3–4 times daily 30 minutes before meals. Tea is not recommended as silymarin is not sufficiently water soluble.
AVAILABILITY
CapsulesOTC
TabletsOTC
Crude drugOTC
TeaOTC
ExtractOTC .
TIME/ACTION PROFILE


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ONSET PEAK DURATION

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PO 5–30 days or more unknown unknown

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NURSING IMPLICATIONS
ASSESSMENT

Assess patients for signs of liver failure such as jaundice, mental status changes, abdominal distention (ascites) and generalized edema.
Monitor liver function tests periodically throughout therapy.
Evaluate consistency and frequency of bowel movements.
POTENTIAL NURSING DIAGNOSES

Knowledge, deficient, related to medication regimen (Patient/Family Teaching).
IMPLEMENTATION

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

Instruct patients in the symptoms of liver failure and to report worsening symptomotolgy promptly to their healthcare provider.
Emphasize the need for blood tests to monitor liver function tests.
Advise patients to abstain from alcohol and to follow a diet consistent with the liver or gall bladder disease being treated.
EVALUATION

Clinical response to therapy can be evaluated by:

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