I was was deficient during one of my pregnancies and got the shots. I felt better very quickly and it only lasted during the pregnancy. My dad who is old has to get shots monthly. It works really well for him. I expect I will have problems eventually since it may run in the family and I'm a strict vegetarian. I hope it works quickly for you.
I was only occult deficient, (meaning it was kinda low and supplementation helped) but my dr said there was a British study recently showing that oral supplementation is as effective as the shots. I don't know if that was specifically for occult or for real deficiency too.
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