Folivit Mechanism of Action

Pharmacology: Pharmacodynamics: Folic acid is the precursor of tetrahydrofolic acid, which is involved as a cofactor for transformylation reactions in the biosynthesis of purines and thymidylates of nucleic acids are required for nucleoprotein synthesis. Impairment of thymidylate synthesis in patients with Folic acid deficiency is thought to account for the defective deoxyribonucleic acid (DNA) synthesis that leads to megaloblast formation and megaloblastic and macrocytic anemias. Folic acid acts on megaloblastic bone marrow to produce a normoblastic marrow; maintenance in erythropoiesis; stimulates WBC and platelet production in folate deficiency anemia. So, Folic acid is used for the treatment of megaloblastic anemias due to a deficiency of Folic acid as seen in anemias of nutritional origin, pregnancy or childhood.
Pharmacokinetics: Absorption/Distribution: Folic acid is absorbed rapidly from the small intestine, mainly from the duodenum and jejunum. Folic acid appears in the plasma approximately 5 to 30 minutes after an oral dose; peak levels are generally reached within 1 hour. Normal serum levels of total folate have been reported to be 5 to 15 ng/mL; normal cerebrospinal fluid levels are approximately 16 to 21 ng/mL. Normal erythrocyte folate levels have been reported to range from 175 to 316 ng/mL. In general, folate serum levels below 5 ng/mL indicate folate deficiency, and levels below 2 ng/mL usually result in megaloblastic anemia.
Metabolism/Excretion: Folic acid is metabolized in the liver to 7,8-dihydrofolic acid and eventually to 5,6,7,8-tetrahydrofolic acid with the aid of reduced diphosphopyridine nucleotide (DPNH) and folate reductases. An oral dose of 5 mg in one study and a dose of 40 mcg/kg of body weight in another study resulted in approximately 50% of the dose appearing in the urine. After a single oral dose of 15 mg, up to 90% of the dose was recovered in the urine. A majority of the metabolic products appeared in the urine after 6 hours; excretion was generally complete within 24 hours. Small amounts of orally administered Folic acid have also been recovered in the feces. Folic acid is also excreted in the milk of lactating mothers.