What is the recommended treatment for a female patient with menorrhagia and iron deficiency anemia, with a hemoglobin level of 8.1 g/dL and a hematocrit of 25%?

Treatment of Iron Deficiency Anemia in a Female with Heavy Menstrual Bleeding

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

Immediate Treatment Protocol

Oral iron supplementation is first-line therapy for this patient with moderate anemia (hemoglobin 8.1 g/dL falls in the WHO moderate anemia category of 8.0-10.9 g/dL). 2

Specific Iron Formulation and Dosing

• Prescribe ferrous sulfate 200 mg (containing 65 mg elemental iron) once daily as the preferred first-line treatment due to its effectiveness and lowest cost compared to all other oral iron formulations. 1
• Once-daily dosing is superior to multiple daily doses because hepcidin levels remain elevated for 48 hours after iron intake, blocking further absorption and increasing gastrointestinal side effects without improving efficacy. 1
• Add vitamin C (ascorbic acid) 500 mg with each iron dose to enhance absorption, which is particularly critical given the severely low iron saturation of 8.49%. 1
• Take iron on an empty stomach for optimal absorption, though taking with food is acceptable if gastrointestinal side effects occur. 1

Alternative Formulations if Needed

• If ferrous sulfate causes intolerable gastrointestinal side effects (constipation, diarrhea, nausea), switch to ferrous gluconate or ferrous fumarate, which are equally effective but typically more expensive. 1
• Every-other-day dosing may be better tolerated for some patients with similar rates of iron absorption if daily dosing is not tolerated. 1

Expected Response and Monitoring

• Check hemoglobin at 4 weeks, expecting a rise of approximately 2 g/dL. 1
• Continue oral iron for 3 months after hemoglobin normalizes (total treatment duration typically 6-7 months) to fully replenish iron stores. 1
• Monitor hemoglobin and red cell indices every 3 months for the first year, then again after another year. 1

When to Switch to Intravenous Iron

Consider IV iron if the patient meets any of these criteria:

• Intolerance to at least two different oral iron preparations despite trying ferrous sulfate, ferrous gluconate, and ferrous fumarate. 1
• Failure of hemoglobin to rise by 2 g/dL after 4 weeks of compliant oral therapy, indicating poor absorption, continued blood loss, or malabsorption. 1
• Hemoglobin <10 g/dL with active inflammatory conditions (though not applicable to this case unless concurrent inflammatory bowel disease or other inflammatory condition is present). 1

Preferred IV Iron Formulations

• Choose IV iron preparations that replace iron deficits in 1-2 infusions rather than multiple infusions to minimize risk and improve convenience. 1
• Ferric carboxymaltose (500-1000 mg single doses delivered within 15 minutes) is a preferred formulation. 1

Addressing the Underlying Cause

Heavy menstrual bleeding must be evaluated and treated concurrently:

• Assess menstrual blood loss first in premenopausal women, as menorrhagia, pregnancy, and breastfeeding account for iron deficiency in 5-10% of menstruating women. 1
• Consider pictorial blood loss assessment charts, which have 80% sensitivity and specificity for detecting menorrhagia. 1
• Screen for celiac disease with antiendomysial antibody and IgA measurement, as this is a common cause of malabsorption in younger patients. 1
• Gastrointestinal endoscopy is NOT indicated in women under 45 years without upper GI symptoms, alarm features, or family history of colon cancer. 2, 1

Treatment of Heavy Menstrual Bleeding

• Heavy menstrual bleeding affects approximately 90% of women with underlying bleeding disorders and can be predicted by clots ≥1 inch diameter, low ferritin, and "flooding" (changing pad or tampon more frequently than hourly). 3
• Hemostatic therapy, hormonal therapy, or surgical interventions may be needed to control menorrhagia and prevent recurrent iron deficiency. 3, 4

Critical Pitfalls to Avoid

• Do NOT prescribe multiple daily doses of oral iron - this increases side effects without improving efficacy due to hepcidin-mediated absorption blockade. 1
• Do NOT stop iron therapy when hemoglobin normalizes - continue for 3 months to replenish stores. 1
• Do NOT overlook vitamin C supplementation when oral iron response is suboptimal, as it significantly enhances absorption. 1
• Do NOT fail to identify and treat the underlying cause (heavy menstrual bleeding) while supplementing iron. 1
• Do NOT continue oral iron indefinitely without response - reassess after 4 weeks and switch to IV iron if hemoglobin fails to rise by 2 g/dL. 1

Failure to Respond

If anemia does not improve after 4 weeks despite compliance:

• Assess for continued blood loss from ongoing heavy menstrual bleeding. 1
• Evaluate for malabsorption syndromes including celiac disease. 1
• Verify patient adherence to therapy. 1
• Consider switching to intravenous iron if oral therapy has failed. 1