What are the recommended dose and duration of Feratab (iron supplement) for a patient with moderate to severe anemia (Hemoglobin level of 7.7)?

Feratab Dosing for Hemoglobin 7.7 g/dL

For a patient with hemoglobin of 7.7 g/dL, prescribe ferrous sulfate (Feratab) 325 mg orally once daily for a minimum of 3 months, but strongly consider intravenous iron instead given the severe anemia (Hb <10 g/dL), as IV iron produces faster hemoglobin increases and better tolerability in this setting. 1

Oral Iron Regimen (If Chosen)

Dosing:

• Feratab (ferrous sulfate) 325 mg orally once daily (contains 65 mg elemental iron) 1
• Alternative: 100-200 mg elemental iron daily, divided into 2-3 doses if better tolerated 2, 3
• Take on empty stomach with vitamin C to enhance absorption 2

Duration:

• Minimum 3 months of continuous therapy 2, 3
• Continue until ferritin reaches >100 ng/mL 2
• Full iron store repletion typically requires 3-6 months 3

Expected Response:

• Hemoglobin should increase approximately 2 g/dL after 3-4 weeks of therapy 1
• Recheck hemoglobin and iron indices at 3-4 weeks 1
• Failure to achieve ≥2 g/dL increase by 3-4 weeks indicates poor compliance, continued blood loss, malabsorption, or misdiagnosis 1

Why IV Iron Should Be Strongly Considered

Your patient's hemoglobin of 7.7 g/dL represents severe anemia where IV iron is superior:

• IV iron shows faster hemoglobin response (7-10 g/L increase vs 4-7 g/L with oral iron) 1
• Better tolerated with fewer gastrointestinal side effects 4
• More effective when hemoglobin is below 10 g/dL 1
• Recommended first-line if active inflammation, malabsorption, or ongoing blood loss present 1

IV Iron Dosing (If Appropriate):

• For body weight <70 kg with Hb 70-100 g/L: total dose 1500 mg IV iron 1
• For body weight ≥70 kg with Hb 70-100 g/L: total dose 2000 mg IV iron 1
• Multiple formulations available with varying infusion schedules 4

Critical Monitoring Protocol

Week 3-4:

• Recheck hemoglobin, ferritin, and transferrin saturation 1
• If hemoglobin increase <2 g/dL, investigate for ongoing blood loss, malabsorption, or non-compliance 1

Month 3:

• Recheck hemoglobin and ferritin 2
• If ferritin remains <100 ng/mL, continue supplementation and investigate underlying causes 2

Weekly until stable:

• Monitor hemoglobin if patient is symptomatic or if considering transfusion 4

Essential Workup Before Treatment

Before starting iron, confirm iron deficiency:

• Check ferritin and transferrin saturation (TSAT) 1
• Iron deficiency defined as: ferritin <30 ng/mL (or <100 ng/mL if inflammation present) and TSAT <20% 4
• Rule out other causes of anemia (B12 deficiency, folate deficiency, chronic disease) 2

Investigate underlying cause:

• Men and postmenopausal women with iron deficiency anemia require gastrointestinal evaluation 5
• Consider bidirectional endoscopy (gastroscopy and colonoscopy) to rule out GI malignancy 3
• Screen for celiac disease with transglutaminase antibody 3

Transfusion Consideration

At hemoglobin 7.7 g/dL, evaluate need for red blood cell transfusion:

• One unit of packed red cells increases hemoglobin by approximately 1 g/dL 4
• Transfusion indicated if patient is symptomatic (tachycardia, shortness of breath, chest pain, altered mental status) 6
• Restrictive transfusion threshold of 7-8 g/dL is safe in most patients, but use clinical judgment based on symptoms 6
• Transfusion does not immediately correct iron deficiency—iron from transfused cells takes 100-110 days to become available 4

Common Pitfalls to Avoid

• Do not delay treatment waiting for complete workup—start iron supplementation immediately while investigating cause 2
• Do not discontinue iron too early—continue for minimum 3 months even if hemoglobin normalizes, as iron stores require longer to replenish 2, 3
• Do not assume oral iron failure without adequate trial—ensure 3-4 weeks of compliant therapy before switching to IV 1
• Do not forget to recheck iron studies—monitor response at 3-4 weeks to ensure efficacy 1
• Do not overlook underlying pathology—severe iron deficiency in adults warrants investigation for GI blood loss or malignancy 3, 5