Is there a ceratin amount of folic acid you should have when on amethia birthcontrol?

Not really: You do not need to worry about folic acid supplementation when on birth control. If you stop birth control and are trying for pregnancy, you should take at least 400 micrograms of folic acid daily to reduce the risk of birth defects like spina bifida. Most women's vitamins or OTC prenatal vitamin would have adequate folic acid.

Standard amount: Your typical multivitamin contains 400 mcg of folic acid which is a sufficient amount. Folic acid has some protective effects for a developing pregnancy were that to occur in spite of you taking the pill. It does not improve the effectiveness of the pill.