CLINICAL MANIFESTATIONS OF HIGH AND LOW PLASMA MAGNESIUM

Abstract

Although a great deal of clinical significance has been attached to variations in blood calcium, variations in blood magnesium have entirely escaped notice. Very little has been known even about what happens when a patient takes an ordinary purgative dose of epsom salt. Matthew Hay¹found that one normal man excreted 28 per cent of the ingested magnesium through the kidneys in twenty-four hours, and Yvon²found 21 per cent. Using a new and convenient method for the quantitative determination of magnesium in blood plasma and urine, we³have found that seven normal men excreted from 40 to 44 per cent (average 42.6 per cent) of the magnesium taken in a single ordinary purgative dose of epsom salt within twenty-four hours after ingestion. However, in spite of the large amount of magnesium absorbed, the concentration of magnesium in the blood plasma (normal, from 1.8 to 2.5 mg.