How to manage iron deficiency anemia in a patient with heavy menstrual bleeding and a decreased hemoglobin level?

Management of Iron Deficiency Anemia in Heavy Menstrual Bleeding

Start ferrous sulfate 200 mg once daily with vitamin C 500 mg to enhance absorption, and continue for 3 months after hemoglobin normalizes to replenish iron stores. 1

Immediate Treatment Approach

• Initiate oral iron therapy immediately with ferrous sulfate 200 mg once daily taken with vitamin C 500 mg, which is the recommended first-line treatment for iron deficiency anemia in menstruating women 1
• All ferrous salts (sulfate, gluconate, fumarate) are equally effective when given in equivalent elemental iron doses, so ferrous sulfate remains the most cost-effective option 2
• Taking iron with meals can minimize gastrointestinal side effects like nausea, though this may slightly reduce absorption 3

Monitoring Treatment Response

• Check hemoglobin at 3-4 weeks - it should rise by approximately 2 g/dL if treatment is effective 1, 2
• If hemoglobin fails to rise appropriately, consider four key possibilities: poor compliance, misdiagnosis, continued blood loss from ongoing heavy menses, or malabsorption 1
• After hemoglobin normalizes, continue monitoring every 3 months for the first year, then once more after another year 2

Duration of Therapy

• Continue iron supplementation for 3 months after hemoglobin normalizes to adequately replenish iron stores - this is critical to prevent rapid recurrence 1, 2
• Premature discontinuation before stores are replenished is a common pitfall that leads to treatment failure 1

When to Escalate to Intravenous Iron

Reserve IV iron for specific situations only 1, 2:

• Intolerance to at least two different oral iron preparations
• Documented malabsorption
• Non-compliance with oral therapy
• Persistent anemia despite adequate oral iron trial and correction of menstrual bleeding

Available IV preparations include iron sucrose, ferric carboxymaltose, and iron dextran, with single-dose formulations preferred by patients to minimize treatment burden 2, 4

Investigating Underlying Causes

• Screen for celiac disease in all premenopausal women with iron deficiency anemia, as this is a common cause of malabsorption 2
• Pursue gastrointestinal investigation if the patient has GI symptoms, family history of colorectal cancer, or persistent anemia after treating the menstrual bleeding and providing iron supplementation 2
• Address the heavy menstrual bleeding itself through gynecologic evaluation and treatment, as ongoing blood loss will prevent resolution of anemia 5, 6

Critical Pitfalls to Avoid

• Do not prescribe more than 200 mg elemental iron daily - excessive dosing increases side effects and paradoxically reduces absorption due to hepcidin elevation 1
• Do not use intramuscular iron administration as it is painful and should be avoided 1
• Do not stop iron therapy when hemoglobin normalizes - continue for 3 months to replenish stores 1
• Do not delay investigation if response is inadequate at 3-4 weeks 1

Expected Outcomes

• Resolution of anemia should be achieved in 80% of patients by 6 months with appropriate treatment 2
• Iron deficiency occurs in 5-10% of menstruating women, making this a common clinical scenario requiring systematic management 2