Management of Iron Deficiency Anemia in Adult Males

Diagnostic Approach

A hemoglobin concentration below the lower limit of normal for the relevant population defines anemia, and a hemoglobin rise ≥10 g/L within 2 weeks of iron therapy strongly suggests absolute iron deficiency even with equivocal iron studies 1
All adult males with newly diagnosed iron deficiency anemia require bidirectional endoscopy (gastroscopy and colonoscopy) as first-line investigation, regardless of the absence of gastrointestinal symptoms, as approximately one-third of men with iron deficiency anemia have an underlying pathological GI abnormality, and about one-third of these abnormalities prove to be malignancies 1, 2
Celiac disease screening with tissue transglutaminase antibody is mandatory in every case, as it accounts for 3-5% of all iron deficiency anemia cases 1, 2, 4

Explicit questioning about all NSAID use, including over-the-counter ibuprofen, naproxen, and aspirin, is necessary, as patients frequently fail to report these medications 3, 4
Anticoagulant and antiplatelet agent use should be investigated, as it can unmask underlying vascular lesions like angiodysplasia 4

Ferrous sulfate 325 mg (65 mg elemental iron) three times daily on an empty stomach is the standard first-line treatment, and adding vitamin C 500 mg with each iron dose enhances absorption 3
Continue iron for 3 months after hemoglobin normalizes to replenish body stores, and target ferritin >50 ng/mL after store repletion 3

Do not stop investigating after finding one cause, as multiple etiologies coexist in 10-15% of patients, and do not accept minor findings as the sole cause without completing lower GI investigation 4
Failing to screen for celiac disease results in missed diagnoses in 3-5% of cases 1, 4

Immediate hospitalization or urgent hematology consultation for consideration of blood transfusion is necessary for hemoglobin <7 g/dL with symptoms, followed by aggressive iron replacement and mandatory bidirectional endoscopy 3