What is the recommended treatment for iron deficiency anemia in males?

Iron Deficiency Anemia in Males: Evaluation and Management

All males with iron deficiency anemia require comprehensive gastrointestinal investigation with both upper endoscopy (with small bowel biopsy) and colonoscopy to identify the source of blood loss, as this is pathologic in men and indicates occult bleeding until proven otherwise. 1

Diagnostic Evaluation

Initial Laboratory Confirmation

• Confirm iron deficiency with MCV < 76 fl and ferritin < 15 mg/dL (or < 45 mg/dL in the presence of anemia per more recent guidance) 1
• Hemoglobin and red cell indices establish the diagnosis 1

Mandatory Gastrointestinal Investigation

For men of all ages, the following investigations are required: 1

• Upper GI endoscopy with small bowel biopsy (to detect celiac disease, H. pylori, gastric lesions)
• Colonoscopy (or CT colonography if colonoscopy not feasible) to exclude colonic pathology including malignancy
• 90% of male patients should undergo both investigations unless a definitive cause is identified with the first test 1

Additional Considerations

• Exclude hematuria to rule out urinary tract tumors, which occasionally present with IDA 1
• Test for H. pylori if IDA persists or recurs after negative endoscopy, and eradicate if present 1
• Consider celiac disease testing (antiendomysial antibody with IgA levels) if not already biopsied 1

Further Investigation if Initial Workup Negative

If bidirectional endoscopy is negative and IDA persists or recurs: 1

• Capsule endoscopy is the preferred test for small bowel examination (highly sensitive for mucosal lesions)
• CT/MR enterography as complementary investigation for inflammatory or neoplastic disease
• Renal tract evaluation if other sources excluded 1

Treatment Approach

Oral Iron Therapy (First-Line)

Initiate oral iron supplementation immediately—do not defer while awaiting investigations unless colonoscopy is imminent. 1

Recommended regimen: 1

• Ferrous sulfate 200 mg once or twice daily (most simple and cost-effective)
• Alternative salts (ferrous fumarate, ferrous gluconate) are equally effective 1
• Lower doses or alternate-day dosing may be as effective and better tolerated if side effects occur 1

Duration: 1

• Continue for 3 months after hemoglobin normalization to replenish iron stores
• Expected hemoglobin rise: 2 g/dL after 3-4 weeks 1

Adjunctive measures: 1

• Consider ascorbic acid (250-500 mg twice daily) to enhance absorption if response is poor, though evidence for effectiveness is limited 1

Parenteral Iron Therapy (Second-Line)

Reserve for: 1

• Intolerance to at least two oral preparations
• Non-compliance with oral therapy
• Malabsorption
• Ongoing blood loss unresponsive to oral iron
• Severe anemia requiring rapid correction

Available formulations: 1

• Iron sucrose (Venofer): 200 mg over 10 minutes, maximum single dose 2
• Ferric carboxymaltose (Ferinject): 1000 mg over 15 minutes 1
• Iron dextran (Cosmofer): 20 mg/kg over 6 hours (higher anaphylaxis risk 0.6-0.7%) 1

Important caveat: Parenteral iron is more expensive, carries anaphylaxis risk, and produces no faster hemoglobin rise at 12 weeks compared to oral therapy, though initial rise may be more rapid. 1

Follow-Up Strategy

Monitoring schedule: 1

• Check hemoglobin response at 4 weeks after initiating therapy 1
• Once normalized: monitor every 3 months for 1 year, then at 2 years 1
• Repeat iron supplementation if hemoglobin or MCV falls below normal 1

Failure to respond indicates: 1

• Poor compliance (most common)
• Continued blood loss
• Malabsorption
• Misdiagnosis

Further investigation warranted if: 1, 3

• Inadequate response to iron replacement therapy
• Recurrent IDA despite treatment
• Hemoglobin and MCV cannot be maintained with supplementation 1

Common Pitfalls

• Do not perform fecal occult blood testing—it is insensitive and non-specific, providing no diagnostic value 1
• Do not delay iron therapy while awaiting endoscopic investigations 1
• Do not assume dietary deficiency alone in males—always investigate for pathologic blood loss 1
• Ensure resuscitation facilities available when administering any intravenous iron due to anaphylaxis risk 1