Folacid

Folacid is a brand name used for folic acid, a synthetic form of the essential B vitamin folate (vitamin B9). Folic acid is a water-soluble vitamin involved in one-carbon metabolism and DNA synthesis. It is supplied as a dietary supplement and in fortified foods; natural folate occurs in leafy greens, legumes, liver, and some fruits.

Medical uses of folacid include prevention and treatment of folate deficiency, which can cause megaloblastic anemia and elevated homocysteine levels. It is especially important for women planning pregnancy or who are pregnant, to reduce the risk of neural tube defects when begun before conception and continued through early pregnancy. Folacid may be prescribed as part of prenatal care or to address confirmed deficiency.

Dosage and administration commonly involve tablet strengths of 0.4 mg (400 mcg) and 1 mg (1000 mcg). The general recommended daily intake for most adults is about 0.4 mg, while pregnancy often calls for around 0.6 mg daily; prenatal supplements typically provide 0.4–0.8 mg. The tolerable upper intake level for adults is 1 mg per day from supplements and fortified foods.

Safety and adverse effects are usually limited, with rare digestive upset or rash. High-dose folic acid can mask signs of vitamin B12 deficiency and may delay diagnosis of pernicious anemia. Folate status can be affected by liver disease, certain medications, and alcohol consumption.

Interactions include reduced effectiveness of methotrexate and altered folate requirements with certain anticonvulsants and metformin.

History and context: Folic acid was identified in the mid-20th century and has since become a standard component of supplements and food fortification programs in many countries to reduce neural tube defects. Folacid represents one of the commercial uses of this nutrient.