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25 Jul 2006

Vitamins and oral contraceptives
Hi there.

I don't know if I'm askiing the right person, but I started running about four weeks ago, and I'm taking some multi-vitamins and magnesium supplements. I heard that anti-biotics, sometimes affect the effectiveness of birh control pills, and that you can become pregnent. But I just want to know, if it is the same with these supliments that I am taking. Will vitamins and magnesium supplements, cause birth control pills, to fail?? I am just a bit concerned, about this, because of what i've heard from other women, when on antibiotics while using oral contraception??

Answer 263 views

01 Jan 0001

Dear Very concerned - high doses of Vit C ( 1000 mg per day) could be risky but not the rest. The reason contraceptives fail when you are on antibiotics is because we use very low doses of hormone and it needs to be absorbed, go through the liver and be excreted in the deodenum and re-absorbed. Antibiotics, some drugs and having diarrhoea interferes with this "second" absorbtion and make the pill less effective. Just remember if you are training very hard that your menstruations can become irregular!
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