Ferritin Test Interactions

Recent iron supplementation does not meaningfully affect ferritin measurement itself (ferritin is a storage protein, not free iron in serum), but it does spike serum iron and transferrin saturation values measured in the same panel, leading to misleading interpretation of overall iron status. A ferritin result drawn shortly after an iron tablet can also be misinterpreted alongside falsely elevated serum iron, suggesting iron stores are repleted when they are not.