folic acid

  • Pharmacy Author:
    Omudhome Ogbru, PharmD

    Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

  • Medical and Pharmacy Editor: Jay W. Marks, MD
    Jay W. Marks, MD

    Jay W. Marks, MD

    Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

What is folic acid-oral, and how does it work (mechanism of action)?

Folic acid and folate are water-soluble forms of vitamin B9 that is naturally found in many of the foods we eat. Folate occurs naturally in food while folic acid is the man-made form of this important vitamin. Common dietary sources of folate include

  • green leafy vegetables,
  • fruits and fruit juices,
  • nuts,
  • beans,
  • peas,
  • dairy products,
  • poultry,
  • meats,
  • eggs,
  • seafood,
  • grains,
  • yeast,
  • beef kidney, and
  • beef liver.

Additionally, folic acid is added to many food products (fortified) and is available as a dietary supplement.

Folic acid is an important vitamin that is needed for the proper development of the human body. Folic acid is needed to make DNA and other genetic material and for the synthesis of red blood cells. Folic acid deficiency can cause megaloblastic anemia, a red blood cell disorder that can cause symptoms of weakness, fatigue, trouble concentrating, irritability, headache, abnormal heartbeats, and shortness of breath. Folic acid is necessary for healthy skin, hair, and nails. Therefore, folic acid deficiency may cause sores in the mouth, and changes in the color of the skin, hair, or fingernails. Additionally, maintaining healthy levels of folic acid during pregnancy is very important. Pregnant women who do not get enough folic acid are at risk of giving birth to babies with neural tube defects such as spina bifida. Folic acid deficiency during pregnancy may also increase the likelihood of having a premature delivery or a low weight baby.

What brand names are available for folic acid-oral?

FA-8, Folacin, Folic Acid, GNC Folic Acid 400, and many more

Is folic acid-oral available as a generic drug?


Do I need a prescription for folic acid-oral?


What are the side effects of folic acid-oral?

WARNING Folic acid supplementation is generally thought to be safe for human use. However, in rare cases, allergic or anaphylactoid reactions have occurred. Patients experiencing any signs or symptoms of a severe allergic reaction including hives, difficulty breathing or swallowing, and shortness of breath should seek emergency medical help.

What is the dosage for folic acid-oral?

For the treatment of folate deficiency megaloblastic anemia or macrocytic anemia

Which drugs or supplements interact with folic acid-oral?


Coadministration of folic acid with cholestyramine (Prevalite, Questran, Questran Light) may decrease the absorption of folic acid. Patients taking both medications are advised to take folic acid 1 hour before or 4-6 hours after cholestyramine.

Folic acid may interfere with methotrexate (Trexall, Rhuematrex, MTX), a medication used to treat certain cancers. Methotrexate works by decreasing the effects of folic acid and therefore, taking these medications together may decrease the effectiveness of methotrexate.

Folic acid supplements may reduce blood levels of certain anti-seizure medications including phenytoin (Dilantin), fosphenytoin (Cerebyx), primidone (Mysoline) and phenobarbital (Luminal) thereby reducing their effectiveness. Also, these medications may also reduce the blood levels of folic acid.

Sulfasalazine (Azulfidine) may decrease the body's ability to absorb folic acid.

Folic acid may decrease the effectiveness of pyrimethamine (Daraprim), a medicine used to treat parasite infections.

Is folic acid-oral safe to take if I'm pregnant or breastfeeding?

Adequate intake of folic acid during pregnancy is very important for the health of the mother and her baby. Clinical evidence shows that fetal neural defects can be prevented with folic acid supplementation in folic acid deficient mothers.

Folic acid is safe for use during pregnancy. However, pregnant women are advised to speak to their doctor or pharmacist before starting supplementation.

Maintaining adequate folic acid intake is important for nursing mothers. Women who are unable to get enough dietary folic acid may require supplementation to achieve adequate intake during lactation. The American Academy of Pediatrics (AAP) considers use of folic acid supplements to be compatible with breastfeeding.

What else should I know about folic acid-oral?

What preparations of folic acid-oral are available?

  • Preservative free oral capsules: 5 and 20 mg
  • Solution for injection: 5 mg/ml (10 ml)
  • Oral tablets: 400 mcg, 800 mcg, 1 mg
  • Preservative free oral tablets: 800 mcg dye free, 400 and 800 mcg

How should I keep folic acid-oral stored?

Folic acid preparations should be stored at room temperature between 15 C and 30 C (59 F and 86 F).


Folic acid, folate, vitamin B9 (FA-8, Folacin, Folic Acid, GNC Folic Acid 400, and many more) is used for the treatment of folate deficiency and its complications, and for the treatment of folic acid deficiency associated with liver disease, kidney dialysis, ulcerative colitis, and alcoholism. Folic acid supplements also are taken by women who are pregnant or planning to become pregnant to prevent birth defects (neural tube defects such as spina bifida) and miscarriage. Side effects, drug interactions, dosing, storage, and pregnancy and breastfeeding safety information should be reviewed prior to taking any medication.

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National Institutes of Health; Office of Dietary Supplements. Folate. December 14, 2012.