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Date of last update: 10/14/2017.

Forum Name: Obstetrics

Question: Vitamin B12 supplements during pregnancy

 teddybear3499 - Mon Feb 15, 2010 3:33 pm

My prenatal vitamin only has 8 mcg of Vitamin B-12. I bought this product by Trivita called Super Sublingual B-12 which has 3000mcg of B-12. It goes straight to your bloodstream when you put it under your tongue. Can I take this much while pregnant? I asked my OB/Gyn( who looked very young by the way; like he was right out of med school.) I showed him the product label and he said it was okay to take it and that if I get too much I will just pee it out. But 3000mcg of B-12 sounds high compared to 8 mcg that is in the prenatal vitamin.

My maternal grandmother had pernicious anemia and I've read it can be hereditary.
Trivita sells this B-12 to the public online. So it is not a prescription. I asked my OB doctor if he could test me for B-12 deficiency and he gave me that deer in headlights look like B-12 deficiency doesn't have anything to do with pregnancy. He said that wasn't in their normal routine labwork and he would have to call and ask how to test for it.
Am I wasting my money taking the B-12 supplement if I am not deficient. I am 29 years old and my brother who is 31 recently had symptoms of B-12 deficiency. He had tingling sensations like pins and needle sensations from his head to his torso. Actually he said he had it even while he lived at home(in high school) but never told anyone. He said he has also had hallucinations. I found out my mother and my aunt take B-12 shots.

I was just wondering if 3000 mcg of B-12 is too much during pregnancy. I took one last night around 1am and forgot I took one and took one today around 1pm.

Would greatly appreciate your input. Thanks!
 Debbie Miller, RN - Sun Feb 28, 2010 3:03 am

User avatar Hello,
We do not recommend megadoses of vitamins in pregnancy. B-12 is one that is hard to absorb and that is why it is often given through injection. Sublingual is supposed to be absorbed better than taking oral tablets. This is why a multivitamin won't supply much of it (going through the stomach). Even sublingual will result in not all of this being absorbed and this is usually the reason for such large amounts - the hope that enough will get through.

B-12 deficiency is not typically screened, as your doctor said, but levels can be checked. If you are not deficient you probably don't need to take the supplements. These are not regulated by the FDA so we really don't know what amount is therapeutic. If you do not have a deficiency, I would advise against the supplement. There are also intrinsic factors that can interfere with the absorption of B-12 and iron. It is recommended you treat these conditions under a doctor's order and after sufficient testing to determine the actual cause of the anemia or B-12 deficiency.

Best wishes.

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