Folic acid

Folic acid

Folic acid is given to treat megaloblastic anemia due to folic acid deficiency. This type of anemia usually occurs in patients who have tropical or nontropical sprue, although it can also result from poor nutritional intake during pregnancy, infancy, or childhood.

 

Pharmacokinetics

Folic acid is absorbed rapidly in the first third of the small intestine, distributed into all body tissues, and metabolized in the liver. Excess folate is excreted unchanged in urine, and small amounts of folic acid are excreted in stool. Folic acid also appears in breast milk. Synthetic folic acid is readily absorbed, even in malabsorption syndromes.

Pharmacodynamics

Folic acid is an essential component for normal RBC production and growth. A deficiency in folic acid results in megaloblastic anemia and low serum and RBC folate levels.

 

Pharmacotherapeutics

Folic acid is used to treat folic acid deficiency. Patients who are pregnant or undergoing treatment for liver disease, hemolytic anemia, alcohol abuse, or skin or renal disorders typically need folic acid supplementation. Serum folic acid levels below 5 ng/ml indicate folic acid deficiency.

Leucovorin is a folic acid derivative used to treat folic acid deficiencies resulting from administration of methotrexate.

 

Drug interactions

• Methotrexate, sulfasalazine, hormonal contraceptives, aspirin, triamterene, pentamidine, and trimethoprim reduce the effectiveness of folic acid.
• In large doses, folic acid may counteract the effects of anticonvulsants, such as phenytoin, potentially leading to seizures. 

Warning!

Adverse reactions to folic acid

Adverse reactions to folic acid include:

• erythema
• itching
• rash
• anorexia and nausea
• altered sleep patterns
• difficulty concentrating
• irritability
• hyperactivity.