Low levels of carbon dioxide cause tetany by altering the albumin binding of calcium such that the ionized (physiologically influencing) fraction of calcium is reduced; one common reason for low carbon dioxide levels is hyperventilation.[3] Low levels of magnesium can lead to tetany.[4][5] Clostridium tetani toxin, via inhibition of glycine-mediated and GABA-ergic neurotransmission, may lead to tetany.