Zinc-Induced Copper Deficiency as a Rare Cause of Neurological Deficit and Anemia.

Upper respiratory infections (URIs) are common and carry a large economic burden due to missed work and school. This has prompted an increased interest in over-the-counter zinc supplementation to enhance immunity and reduce illness duration. Zinc's antiviral and anti-inflammatory effects have led to its inclusion in popular URI medications and a surge in supplement sales, particularly among the elderly.