The pathologic physiology of certain symptoms in uremic patients remains a mystery. It is generally held that endproducts of metabolism which accumulate in the body lead to depression of the central nervous system, manifested clinically by drowsiness and eventually coma. These symptoms have been reported in patients with renal disease who have been given large doses of magnesium sulfate,1 and a central nervous system depressant effect of magnesium has been utilized in certain clinical situations for a number of years. The literature on serum levels of magnesium in renal disease is confusing; some studies have shown decreased values, while others have shown markedly increased values.2 Furthermore, studies of the relationship of the serum levels of nitrogenous materials, calcium, and potassium to serum magnesium are incomplete.
It is the purpose of this paper to clarify the relationship of serum magnesium to various phases of renal disease and to other