How is folate deficiency treated?

Treatment of Folate Deficiency

Folate deficiency should be treated with oral folic acid 5 mg daily for a minimum of 4 months, after first excluding vitamin B12 deficiency to avoid masking neurological complications. 1

Diagnosis Before Treatment

Before initiating folate replacement therapy:

• Check vitamin B12 status to rule out deficiency
• Measure serum folate (<10 nmol/L indicates deficiency) or red blood cell folate (<305 nmol/L indicates tissue deficiency) 1
• Consider measuring homocysteine (>15 μM suggests functional deficiency) 1

Treatment Protocol

First-Line Treatment

• Oral administration is preferred 2
• Dosage: 5 mg folic acid daily for a minimum of 4 months 1
• Continue until the underlying cause of deficiency is corrected 1

Special Populations

• Chronic hemodialysis patients: 1-5 mg folic acid daily 1
• Pregnant women: 400 μg/day periconceptionally (for neural tube defect prevention) 1
• Patients on medications affecting folate metabolism (anticonvulsants, methotrexate, sulfasalazine): Require supplementation 1, 3

Alternative Routes

• If oral route is ineffective or not tolerated, folic acid can be given subcutaneously, IV, or IM at 0.1 mg/day 1

Monitoring

• Recheck folate levels within 3 months after starting supplementation to verify normalization 1
• Monitor clinical symptoms and blood picture for improvement 2
• When clinical symptoms have subsided and blood picture normalizes, switch to maintenance dosing 2

Maintenance Therapy

• After correction of deficiency, maintain with:
  • 0.4 mg daily for adults
  • 0.8 mg daily for pregnant and lactating women 2
• Never use less than 0.1 mg/day for maintenance 2

Important Cautions

• Always rule out vitamin B12 deficiency before starting folate therapy - High-dose folate can mask the hematologic manifestations of B12 deficiency while allowing neurological damage to progress 1, 4
• Doses greater than 1 mg daily do not enhance hematologic effect, with excess being excreted unchanged in urine 2
• The upper limit for folic acid is set at 1 mg/day to minimize risk of masking B12 deficiency 1
• Higher maintenance doses may be needed in patients with alcoholism, hemolytic anemia, anticonvulsant therapy, or chronic infection 2

Special Considerations

• In inflammatory bowel disease patients on methotrexate: 5 mg once weekly 24-72 hours after methotrexate, or 1 mg daily for 5 days per week 1
• For patients on sulphasalazine: Regular monitoring and supplementation may be required 1
• Patients with malabsorption can usually absorb oral folic acid despite inability to absorb food folates 2

By following this treatment protocol and monitoring appropriately, folate deficiency can be effectively corrected while minimizing potential risks associated with therapy.