Levomefolic acid (INN) is the metabolite of folic acid (Vitamin B9) and it is a predominant active form of folate found in foods and in the blood circulation, accounting for 98% of folates in human plasma [A19276]. It is transported across the membranes including the blood-brain barrier into various tissues where it plays an essential role in the DNA synthesis, cysteine cycle and regulation of homocysteine, where it methylates homocysteine and forms methionine and tetrahydrofolate (THF). Levomefolate is approved as a food additive and is designated a GRAS (generally regarded as safe) compound [L773]. It is available commercially as a crystalline form of the calcium salt (Metafolin(R)), which has the stability required for use as a supplement [A19276]. Supplementation of levomefolic acid is desired over folic acid due to reduced potential for masking vitamin B12 deficiency symptoms.
For the treatment and prevention of folate deficiency and for use as an antidote against folic acid antagonists. Contained in oral contraceptives to reduce the risk of neural tube defects arising from folic acid deficiency for pregnant women who conceived during use or shortly after the discontinuation of the product. Being studied for use as a treatment for cardiovascular diseases [A19273] and adjunct therapy for patients undergoing antidepressant pharmacotherapy [A19271, A19272].
Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison
T, Liu P, Ly S, Frolkis A, Pon A, Banco K, Mak C, Neveu V, Djoumbou Y, Eisner R, Guo AC, Wishart DS.
Nucleic Acids Res. 2011 Jan; 39 (Database issue):D1035-41. | PMID:21059682