Copper deficiency and microcytic anemia resulting from prolonged ingestion of over-the-counter zinc.

Isolated copper deficiency occurred in a 57-yr-old man who had ingested massive quantities of zinc for more than 18 months. The patient presented with microcytic anemia and had normal gastrointestinal function with no evidence of occult blood loss. Dietary zinc in large doses leads to copper deficiency by antagonizing copper absorption. With discontinuance of zinc, the anemia and hypocupremia promptly corrected. The relationship between zinc, copper deficiency, and iron metabolism is reviewed.