How much iu of vitamins a should i take for acne?

Not helpful: Vitamins not for acne as a general rule. Vitamins are designed to be used to replace things that are not present in your diet or you don't get normally. In the us and most developed countries vitamins provide a nice yellow color to your urine and are excreted. Nutraceutical industry is bigger than pharmaceutical industry and don't require scientific proof to advertise. Save money eat healthy.

Not effective : Vitamins in general arenot effective unless you are talking about vitamin a derivatives e.g. Retinoids. I recommend seeing a dermatologist for that treatment.

Don't do it: Retinoic acid derivatives and Isotretinoin are both derived from vitamin a and are treatment standards for acne. However, if you overdose yourself on vitamin a itself, you will simply make yourself seriously sick. If your acne does not respond to over-the-counter treatments like topical benzoyl peroxide, it can be managed medically by a competent physician.