The iron-deficiency anemia is a common disorder worldwide. It is widely treated with oral iron supplements as ferrous sulfate compound in pill or tablet form, and continuous therapy can induce gastric diseases. The diagnosis of this unusual drug-induced disease is based on the endoscopic findings and the histopathological biopsy examination, because the clinical symptoms are vague and non-specific. Herein we report five cases of iron pill-induced gastritis after oral ferrous sulfate administration.The aim of this report is to underline that iron pill-induced gastritis is an under-diagnosed entity that must be kept in mind when patients undergo chronic iron-pill therapy because it can carry severe upper digestive tract complications. Moreover, we would speculate about the potential tumorigenic role of iron intake in iron-induced gastric inflammation.