Which of the following is a common source of iron poisoning?

• A. Oral iron supplementation preps
• B. Vitamin D supplements
• C. Calcium carbonate
• D. Potassium chloride

Answer: (A)

Iron poisoning most often comes from accidental ingestion of oral iron supplements, especially by children. These products deliver a large amount of elemental iron in a small, easy-to-swallow dose, and a few tablets can overwhelm the body's ability to safely bind and transport iron. When iron overload occurs, it damages the GI tract first and then other organs, leading to a progression of symptoms that can be severe: early GI irritation with vomiting and abdominal pain, a temporary improvement, then metabolic disturbances like acidosis, low blood pressure, and possible liver injury. This pattern and the high toxicity potential of common iron-containing products make oral iron supplements the classic source of acute iron poisoning. Other substances listed, such as vitamin D supplements, calcium carbonate, or potassium chloride, do not cause iron overdose and are not typical sources of this poisoning.