Folic acid is a member of the vitamin B group and is the substrate for the production of tetrahydrofolate by enzymatic reduction in vivo. Tetrahydrofolate is a coenzyme for various metabolic pathways including purine and pyrimidine nucleotide synthesis, and ultimately DNA synthesis. It is also involved in some amino acid conversions, and in the formation and utilisation of formate.

Presentation 

Blister pack of 10×10’s tablets and Jar of 1000’s Tablets

Indications:

For treatment of folic acid deficiency, megaloblastic anaemia and in anemias of nutritional supplements, pregnancy, infancy, or childhood. Folate deficiency is a consequence of inadequate dietary intake, malabsorption, or increased utilisation in conditions such as pregnancy, lactation, haemolytic anaemia, hyperthyroidism, exfoliative dermatitis, and chronic infection. Folic Acid is also indicated for prophylaxis of folate deficiency resulting from renal dialysis, pregnancy and lactation when the mother is malnourished.

Pharmacological class

Vitamins and trace elements

Pharmacological properties

Folate supplementation

Mechanism of Action

Folic acid, as it is biochemically inactive, is converted to tetrahydrofolic acid and methyltetrahydrofolate by dihydrofolate reductase. These folic acid congeners are transported across cells by receptor-mediated endocytosis where they are needed to maintain normal erythropoiesis, synthesize purine and thymidylate nucleic acids, interconvert amino acids, methylate tRNA, and generate and use formate.

Side effects

Folic acid is generally well tolerated although uncommon; nausea diarrhoea, flatulence and gastro-intestinal disturbances have been associated with folic acid therapy. Hypersensitivity reactions such as bronchospasm, erythema, fever rash or itching have been reported rarely.

Contraindication

Hypersensitivity to folic acid, megaloblastic anaemia resulting from cyanocobalamin (Vitamin B12) deficiency should not be treated with folic acid as the neurological defects of vitamin B12 deficiency will not be alleviated, and may become irreversible. Caution is advised in patients who may have folate-dependant tumours.

Drug interactions

Folic acid may interact with antacids which contain aluminium or magnesium, antibiotics and cholestyramine, sulphonamides including sulphasalazine and zinc supplements. Folate depletion is a side effect of folate antagonists such as 5-fluorouracil, methotrexate, trimethoprim, Pyrimethamine and sulphonamides.