Folic Acid Dosing for Specific Medical Conditions
Although the recommended dietary allowances have been clearly established, the best doses of
folic acid for other uses are less clear.
Pregnant women with a history of a neural tube defect (such as
spina bifida) are usually instructed to take a high folic acid dose, 4 mg (4000 mcg) per day, starting one month before conception and continuing at least through the
first trimester. Women taking certain medications that can increase the risk of neural tube defects (such as
seizure medications) may also need a higher folic acid dose.
For treating hyperhomocysteinemia, studies have used folic acid doses ranging from 500 mcg (0.5 mg) to 5000 mcg (5 mg). In general, it seems that doses of 800 to 1000 mcg are probably sufficient for lowering homocysteine levels.
General Information on Dosing for Folic Acid
Some considerations for people taking folic acid include:
- In general, it is recommended not to take more than 1000 mcg of folic acid daily with your healthcare provider's approval, since higher doses can "mask" the signs of a vitamin B12 deficiency.
- Since it is important to take folic acid before conception (and since so many pregnancies are unplanned), it is often recommended that women of childbearing age take a supplement or multivitamin with 400 mcg of folic acid daily.
- If you are unsure about anything related to your dosage or folic acid dosing in general, please talk with your healthcare provider.