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    Milk Thistle and Birth Control Pills
    newgirl2010 posted:
    I recently picked up a pack of detox tea. I have been drinking it all week a few cups a day, and I noticed one of the ingredience is milk thistle (1000mg). Upon some research there is an apparent risk of decreased effectiveness of bcp. Any real truth to this? Just speculation? In the supplement world, I have heard of st. john's wort as being a bcp risk, but never any other supplements. I will cease my use of this tea, but now I am really concerned. Thank you.
    newgirl2010 responded:
    great, my tea also contains dandelion...which apparently also reduces the pill's effectiveness. What? Why have i never heard of this?
    newgirl2010 responded:
    Sorry to bump this question. I am just hoping gail or jane can provide insight. I have finished my pill pack. I drank the tea last week for 3-4 days (no intercourse during those days). I did, however, have intercourse last night (first night of placebo). It think it would be overly paranoid to take Plan B. That will just screw up my period and succumbing to my paranoia. But I am scared. I have also read that women on bcp should refrain from licorice. are these herbs a serious threat to bcp or just conjecture of what "might" or "possibly" could happen--but no evidence it ever has.
    georgiagail replied to newgirl2010's response:
    The concern over milk thistle and birth control pills actually focuses on the milk thistle and estrogen based medications used to treat menopause (i.e, Premarin, for example) and estrogen based birth control pills and estrogen-receptor breast cancers (Tamoxifen).

    In one case, it increases the amount remaining in the body (the Tamoxifen) in the other, (estrogen based birth control, estrogen used in hormone replacement therapy), it may decrease this.

    "Tamoxifen (Nolvadex)
    Interaction Rating: Moderate Be cautious with this combination.
    Talk with your health provider.
    Milk thistle might increase how much tamoxifen is absorbed by the body. Before taking milk thistle, talk to your healthcare provider if you are taking tamoxifen.

    Interaction Rating: Minor Be cautious with this combination.
    Talk with your health provider.
    Milk thistle might decrease hormones in the body. Milk thistle might help the body break down estrogen pills to get rid of them. Taking milk thistle along with estrogens might decrease the effectiveness of estrogen pills. Milk thistle contains a chemical called silymarin. Silymarin might be the part of milk thistle that helps the body break down estrogens.

    Some estrogen pills include conjugated equine estrogens (Premarin ), ethinyl estradiol, estradiol, and others."

    What type of birth control pills are you on? Not all oral contraceptives contain estrogen.

    It is unlikely drinking this tea for such a short period of time (just 3-4 days) had any negative effect on your birth control even if your product is a estrogen based oral contraceptive.

    newgirl2010 replied to georgiagail's response:
    Thank you for responding. I am taking orthotricylen lo (low estrogen pill). My pack ended on saturday. I was drinking the tea last week during the day (I take my pill at night)--if that means anything. As I mentioned, I had intercourse last night, but not during the days I was drinking the tea. But in theory, I could have ovulated due to the milk thistle interaction and last night could have caused pregnancy.

    Worst case scenario, if the pill lost effectiveness, i ovulated, and had intercourse last night...knowing that it takes a few days for implantation to occur and the body to realize it is pregnant, if i get my withdrawal period like usual this I okay? or could i still be pregnant due to the lag time in implantation?

    Wow...I am just shocked at this information. The pharmacist looked at me like i was crazy when i asked.
    newgirl2010 replied to newgirl2010's response:
    I have done some more research. It appears that getting milk thistle is tea form is much less concentrated. I have decided that the four days (roughly ten tea bags) I consumed will hopefully not decrease my estrogen levels to a point of ovulation. If milk thistle and red clover caused the pill to lose effectiveness, I think there would be at least articles about women becoming pregnant while on a detox regime. I have not seen such articles.

    Furthermore, to take Plan B (which I could still do) would further delay my period...which is due early Wednesday AM. I feel confident I will get my period as expected, however I am still confused whether or not implantation can occur during my withdrawal bleed--thus, not making my period a true indicator that I am in the clear. The intercourse took place on sunday. If anyone has any insight into that question, please respond.

    I hope my post has alerted some women of the potential problems with the use of herbal supplements.
    georgiagail replied to newgirl2010's response:
    I agree with your conclusion that the amount and the length of time you took this product would have a minimal negative effect on your birth control.


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