What if you take two prenatal vitamins in one day?

If this is a one time occurance, there is no need to worry. You would not want to do this on a regular basis, as overdosing on certain vitamins and minerals is no recommended. Many vitamins can be taken in larger doses than the recommended amount given on the bottle. Vitamin C, for example, can usually be taken in 2500 mg doses, as most people are deficient. Nevertheless, in the case of a prenatal, don't overdose. If you think you need extra vitamins or minerals, get them from whole foods, or consult an ND.