TURUGBY
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Milk thistle may interfere with the following medications, because both milk thistle and these medications are broken down by the same liver enzymes:
Allergy drugs -- such as fexofenadine (Allegra)
Drugs for high cholesterol -- such as lovastatin (Mevacor, Altocor)
Anti-anxiety drugs -- including alprazolam (Xanax), diazepam (Valium), and lorazepam (Ativan)
Antiplatelet and anticoagulant drugs (blood thinners) -- including clopidogrel (Plavix) and warfarin (Coumadin)
Some cancer drugs
Animal studies suggest that milk thistle may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be increased in the blood, and may cause increased effects or adverse reactions. Many types of drugs may be affected.
Milk thistle may interact with hormonal agents. Silymarin and vitamin E have been reported to prevent amiodarone toxicity in animal studies. Milk thistle may chelate iron and slow calcium metabolism.
There are no interactions or contra-indications with medication listed for milk thistle extract. However, there is a chance that silibinin, a component of silymarin, may interfere with certain drugs such as oral contraceptives (7).
The CEU received some information from the NHS drug information regarding milk thistle and oral contraceptives. It stated that there may be an interaction with estrogens and therefore this may cause an interaction between the herbal remedy and OC. As a cautionary note, NHS drug information suggested that, unless it is considered essential, milk thistle is probably best avoided in women using hormonal contraception because of the potential for interaction with estrogens and progestogens. The CEU could find no evidence to support or refute this claim, as no studies have appeared to have looked directly at the interaction between milk thistle and oral contraception.
Many practitioners recommend MILK THISTLE to improve efficient hormone detoxification. This may be helpful in a wide variety of women's hormonal problems: PMS, peri-menopausal symptoms and acne.
Silybin, a major constituent of the milk thistle, is used to treat several liver disorders. Silybin inactivated purified, recombinant cytochromes P450 (P450) 3A4 and 2C9 in a mechanism-based manner. The inactivations were time-, concentration-, and NADPH-dependent. The inactivation of the 7-benzyloxy-4-(trifluoromethyl-)coumarin O-debenzylation activity (P450 3A4) was characterized by a K(I) of 32 microM, a k(inact) of 0.06 min(-1), and a t(1/2) of 14 min. Testosterone metabolism to 6-beta-hydroxytestosterone (P450 3A4) was also inactivated with a K(I) of 166 microM, a k(inact) of 0.08 min(-1), and a t(1/2) of 9 min. The 7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation activity of purified human P450 2C9 was inactivated with a K(I) of 5 microM, a k(inact) of 0.14 min(-1), and a t(1/2) of 7 min. Parallel loss of heme was observed with both P450s. Activity of both P450 enzymes was not recovered after removal of silybin either by dialysis or by spin gel filtration. In addition, silybin inhibited the glucuronidation of 7-hydroxy-4-trifluoromethylcoumarin catalyzed by recombinant hepatic UDP-glucuronosyltransferases (UGTs) 1A1, 1A6, 1A9, 2B7, and 2B15, with IC(50) values of 1.4 microM, 28 microM, 20 microM, 92 microM, and 75 microM, respectively. Silybin was a potent inhibitor of UGT1A1 and was 14- and 20-fold more selective for UGT1A1 than for UGT1A9 and UGT1A6, respectively. Thus, careful administration of silybin with drugs primarily cleared by P450s 3A4 or 2C9 is advised, since drug-drug interactions cannot be excluded. The clinical significance of in vitro UGT1A1 inhibition is unknown.
just some food for thought, My conclusions is to continue taking milkthistle, but at night after the peak levels of DS are no longer in my system for that day. Thoughts?
Allergy drugs -- such as fexofenadine (Allegra)
Drugs for high cholesterol -- such as lovastatin (Mevacor, Altocor)
Anti-anxiety drugs -- including alprazolam (Xanax), diazepam (Valium), and lorazepam (Ativan)
Antiplatelet and anticoagulant drugs (blood thinners) -- including clopidogrel (Plavix) and warfarin (Coumadin)
Some cancer drugs
Animal studies suggest that milk thistle may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be increased in the blood, and may cause increased effects or adverse reactions. Many types of drugs may be affected.
Milk thistle may interact with hormonal agents. Silymarin and vitamin E have been reported to prevent amiodarone toxicity in animal studies. Milk thistle may chelate iron and slow calcium metabolism.
There are no interactions or contra-indications with medication listed for milk thistle extract. However, there is a chance that silibinin, a component of silymarin, may interfere with certain drugs such as oral contraceptives (7).
The CEU received some information from the NHS drug information regarding milk thistle and oral contraceptives. It stated that there may be an interaction with estrogens and therefore this may cause an interaction between the herbal remedy and OC. As a cautionary note, NHS drug information suggested that, unless it is considered essential, milk thistle is probably best avoided in women using hormonal contraception because of the potential for interaction with estrogens and progestogens. The CEU could find no evidence to support or refute this claim, as no studies have appeared to have looked directly at the interaction between milk thistle and oral contraception.
Many practitioners recommend MILK THISTLE to improve efficient hormone detoxification. This may be helpful in a wide variety of women's hormonal problems: PMS, peri-menopausal symptoms and acne.
Silybin, a major constituent of the milk thistle, is used to treat several liver disorders. Silybin inactivated purified, recombinant cytochromes P450 (P450) 3A4 and 2C9 in a mechanism-based manner. The inactivations were time-, concentration-, and NADPH-dependent. The inactivation of the 7-benzyloxy-4-(trifluoromethyl-)coumarin O-debenzylation activity (P450 3A4) was characterized by a K(I) of 32 microM, a k(inact) of 0.06 min(-1), and a t(1/2) of 14 min. Testosterone metabolism to 6-beta-hydroxytestosterone (P450 3A4) was also inactivated with a K(I) of 166 microM, a k(inact) of 0.08 min(-1), and a t(1/2) of 9 min. The 7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation activity of purified human P450 2C9 was inactivated with a K(I) of 5 microM, a k(inact) of 0.14 min(-1), and a t(1/2) of 7 min. Parallel loss of heme was observed with both P450s. Activity of both P450 enzymes was not recovered after removal of silybin either by dialysis or by spin gel filtration. In addition, silybin inhibited the glucuronidation of 7-hydroxy-4-trifluoromethylcoumarin catalyzed by recombinant hepatic UDP-glucuronosyltransferases (UGTs) 1A1, 1A6, 1A9, 2B7, and 2B15, with IC(50) values of 1.4 microM, 28 microM, 20 microM, 92 microM, and 75 microM, respectively. Silybin was a potent inhibitor of UGT1A1 and was 14- and 20-fold more selective for UGT1A1 than for UGT1A9 and UGT1A6, respectively. Thus, careful administration of silybin with drugs primarily cleared by P450s 3A4 or 2C9 is advised, since drug-drug interactions cannot be excluded. The clinical significance of in vitro UGT1A1 inhibition is unknown.
just some food for thought, My conclusions is to continue taking milkthistle, but at night after the peak levels of DS are no longer in my system for that day. Thoughts?
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