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FOLIC ACID - a patient's guide


Folic acid has been shown to reduce the incidence of spina bifida when taken before conception and in early pregnancy. This article profiles the supplement.

USE: Folate deficiency; lower incidence of spina bifida if taken during pregnancy.

Folic acid is prescribed for the treatment of megaloblastic anaemia; replacement therapy during pregnancy and breastfeeding - reducing the incidence of birth defects (esp. spina bifida).

Folic acid (folate) is used for the synthesis of DNA bases (purine and pyrimidine) where deficiency can result in faulty cell division and maturation. Deficiency can be due to factors such as poor diet, alcohol abuse, increased requirements (pregnancy), malabsorption, and certain drugs with presenting signs of weight loss, sore tongue, diarrhoea and neurological problems.


Undiagnosed megaloblastic anaemia (rule out Vit-B12 deficiency).

Folate-dependent tumours.

Side effects:

Rarely: stomach problems, diarrhoea, sleep disturbances, irritability, and skin rash (stop treatment).


Anti-epileptics (phenobarbitone, phenytoin) are possibly reduced in combination with folic acid. Other interactions include sulphasalazine, trimethoprim, methotrexate and pyrimethamine.

Patient information:

  • Follow the instructions on the label of this medicine
  • Do not stop taking this medicine unless directed (even if you feel better)
  • Take 4 weeks pre-conception to 3 months post-conception for reducing risk of birth defects
  • Contact your doctor if side effects are severe (skin rash) or ongoing (diarrhoea)

See also:

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