With the increased concern surrounding diuretic-induced electrolyte losses, numerous articles have surfaced investigating the detrimental effects of diuretic-induced hypomagnesemia. This article's purpose is to familiarize the reader with hypomagnesemia and hypermagnesemia. Methods of detection, symptoms, etiologies, and potential modes of therapy are discussed. Particular attention is given to the role magnesium plays in the cardiovascular system with additional discussion on lipid alterations and glucose handling. Specific suggestions are given for the inpatient and outpatient treatment of hypomagnesemia.