Blue lunulae: Argyria and hypercopprecaemia

SUMMARY A 42‐year‐old woman presented with blue lunulae in association with argyria and hypercopprecaemia. The argyria was caused by the regular ingestion of colloidal silver in water over an extended period of time. The raised copper may have contributed to the nail discolouration, and was believed to be due either to ingestion of copper‐containing multivitamin tablets or as an acute‐phase reactant. We believe that the ease of access to, and lack of stringent regulatory controls over, food supplements and alternative medicines may cause similar cases in the future. We therefore recommend that all patients should be routinely questioned on their use of over‐the‐counter preparations and alternative medicines.