What is the treatment for iron deficiency anemia with low iron and ferritin levels?

Treatment for Iron Deficiency with Serum Iron 38 and Ferritin 11

Start oral iron supplementation immediately with ferrous sulfate 100-200 mg daily, given your ferritin of 11 ng/mL confirms iron deficiency requiring treatment. 1

Initial Treatment Approach

Your ferritin level of 11 ng/mL is well below the threshold of 15 ng/mL that confirms depleted iron stores, making iron supplementation clearly indicated. 1

Oral Iron Therapy (First-Line)

Dosing regimen:

• Ferrous sulfate 200 mg three times daily is the traditional approach, though 100-200 mg daily in divided doses is effective 1
• Alternate-day dosing (e.g., 200 mg every other day) may provide better iron absorption with fewer gastrointestinal side effects based on recent evidence 1
• Ferrous gluconate or ferrous fumarate are equally effective alternatives if ferrous sulfate is not tolerated 1

Duration:

• Continue for at least 3 months after hemoglobin normalizes to adequately replenish iron stores 1
• Expect hemoglobin to rise by approximately 2 g/dL after 3-4 weeks of treatment 1

Enhancing absorption:

• Consider adding ascorbic acid (vitamin C) to enhance iron absorption, particularly if response is suboptimal 1
• Avoid taking iron with inhibitors of absorption (tea, coffee, calcium supplements) 1

Common Side Effects to Anticipate

Gastrointestinal side effects occur frequently and include constipation, diarrhea, and nausea. 1 If these develop, consider switching to alternate-day dosing or trying a different iron salt formulation. 1

When to Consider Intravenous Iron

IV iron is indicated if: 1

• Intolerance to at least two different oral iron preparations 1
• Malabsorption conditions (celiac disease, post-bariatric surgery, inflammatory bowel disease) 2
• Ongoing blood loss that cannot be controlled 1
• Failure to respond to oral therapy after adequate trial 1
• Chronic inflammatory conditions (chronic kidney disease, heart failure, inflammatory bowel disease) 2

IV iron formulations:

• Ferric carboxymaltose is the best-studied option, given as 1 gram over 15 minutes, and has been associated with reduced hospital stay and mortality in critically ill patients 1
• Iron sucrose and ferric gluconate are alternatives but may require multiple administrations 1
• Avoid high molecular weight iron dextran due to highest risk of reactions 1
• Serious reactions are rare (<1:250,000 administrations) but can be life-threatening, so administration requires monitoring 1

Monitoring Treatment Response

Recheck laboratory values:

• Repeat hemoglobin and ferritin 8-10 weeks after starting treatment 1
• Do not check ferritin earlier after IV iron as levels will be falsely elevated 1
• After normalization, monitor hemoglobin every 3 months for the first year, then annually 1

Treatment failure indicators:

• Hemoglobin fails to rise by 2 g/dL after 3-4 weeks 1
• Most common causes: poor compliance, continued blood loss, malabsorption, or misdiagnosis 1

Critical Next Steps: Identify the Underlying Cause

You must investigate why iron deficiency developed: 1

• Menstruating women: Heavy menstrual bleeding is the most common cause (affects 5-10% of women) 1, 2
• All other adults and post-menopausal women: Gastrointestinal blood loss must be excluded with upper endoscopy and colonoscopy 1
• Consider dietary insufficiency, particularly in vegetarians 1
• Screen for malabsorption disorders (celiac disease, atrophic gastritis, H. pylori infection) 2, 3
• Review medications, especially NSAIDs and anticoagulants 2

Important Caveats

• Never supplement iron if ferritin is normal or elevated without clear indication, as this is potentially harmful 1
• Iron overload risk is minimal with oral therapy in the setting of true deficiency, but avoid chronic supplementation once stores are replenished 1
• If hemoglobin cannot be maintained after initial correction, further investigation is mandatory rather than indefinite iron supplementation 1