Various trace elements with an important role in oxidative stress or membrane physiology were measured in 42 patients with essential hyperhidrosis (EH). A healthy control group of 37 subjects was included in the study. Levels of selenium (Se), zinc (Zn), copper (Cu), iron (Fe), magnesium (Mg) and calcium (Ca) were measured in both plasma and erythrocytes. Erythrocyte levels of Se, Fe, Cu, Zn and Ca were significantly higher in patients with EH than controls. In contrast, plasma levels of Cu, Ca and Mg were significantly lower in patients than controls. The increased levels of erythrocyte Cu and Fe may be due to increased intracellular oxidative stress, but the increased Se ...