After a thermal trauma similar changes of Mg and Zn levels in serum are observable. During the initial period of shock the concentration of both elements increases as a consequence of damage of cellular and subcellular compartments. During the catabolic phase a deficiency syndrome occurs as a result of renal excretion, loss through the wound secretion, and demarcation of necrotic tissue. On the other hand increasing requirements of Mg and Zn appear because of the anabolic process of wound healing. From these reasons a substitution of both elements is recommendable in all cases of proved deficiency after burns.