Treatment for Heavy Menstrual Bleeding with Severe Iron Deficiency (Ferritin 5)
Start oral ferrous sulfate 200 mg once daily immediately, continue for 3 months after hemoglobin normalizes, and simultaneously address the underlying heavy menstrual bleeding to prevent recurrence. 1
Immediate Iron Replacement
Begin ferrous sulfate 200 mg once daily as the most cost-effective first-line treatment for iron deficiency anemia secondary to menorrhagia 1
Once-daily dosing is superior to multiple daily doses because it improves gastrointestinal tolerance while maintaining equal or better iron absorption due to hepcidin regulation 1
Add vitamin C (ascorbic acid) 500 mg with each iron dose to enhance absorption, which is particularly critical when iron stores are severely depleted (ferritin 5) 1, 2
If ferrous sulfate is not tolerated, switch to ferrous gluconate or ferrous fumarate, which are equally effective alternatives 1, 2
Liquid iron preparations may be better tolerated if tablets cause gastrointestinal side effects 2
Critical Duration of Therapy
Iron therapy must continue for 3 months after hemoglobin normalizes to fully replenish body iron stores 1, 2
Stopping iron when hemoglobin normalizes is a critical pitfall that leads to recurrence, as body stores remain depleted even when hemoglobin appears normal 1, 2
The treatment goal is to restore both hemoglobin levels and mean corpuscular volume (MCV) to normal ranges while replenishing iron stores 2
Expected Response and Monitoring
Hemoglobin should rise by approximately 2 g/dL after 3-4 weeks of compliant oral iron therapy 1
Monitor hemoglobin and red cell indices at 3-month intervals for the first year, then again after another year 1, 2
If hemoglobin or MCV falls below normal during follow-up, restart iron supplementation and check ferritin in doubtful cases 1, 2
When to Switch to Intravenous Iron
Consider intravenous iron if the patient cannot tolerate at least two different oral iron preparations, or if oral iron fails to improve ferritin levels after 4 weeks of compliant therapy 1
Parenteral iron should not be used as first-line therapy unless there is documented intolerance to at least two oral preparations 1, 2
All IV iron formulations have similar safety profiles, with true anaphylaxis being rare (0.6-0.7%) 1
Single-dose IV iron formulations are preferred by patients as they reduce the burden of multiple appointments and improve adherence 3
Addressing the Underlying Heavy Menstrual Bleeding
The underlying menorrhagia must be simultaneously addressed to prevent recurrence of iron deficiency 1
Tranexamic acid is an effective treatment option that reduces menstrual blood loss and has been shown to significantly increase hemoglobin and ferritin levels in women with heavy menstrual bleeding 4
Menstrual blood loss can be quantified using pictorial blood loss assessment charts, which have 80% sensitivity and specificity for detecting menorrhagia 1
Failure to Respond Algorithm
If hemoglobin fails to rise by 2 g/dL after 4 weeks despite compliant oral iron therapy, verify adherence and assess for continued menstrual blood loss or malabsorption 1
If anemia does not resolve within 6 months despite appropriate iron therapy and menorrhagia control, reassess for ongoing occult blood loss from gastrointestinal sources 1
Further investigation with upper endoscopy and colonoscopy may be necessary if iron deficiency persists despite treatment 1
Common Pitfalls to Avoid
Do not prescribe multiple daily doses of oral iron, as this increases gastrointestinal 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, as premature discontinuation leads to recurrence 1, 2
Do not overlook vitamin C supplementation when oral iron response is suboptimal 1, 2
Do not use parenteral iron as first-line unless there is documented intolerance to at least two oral preparations 1, 2