Summary By Hans R. Larsen MSc ChE
ST. JOHN’S, CANADA. Canadian doctors report on two cases of severe muscle cramps which were relieved by the intravenous infusion of magnesium sulfate. The first case involved a 17-year-old soldier who had been exercising too strenuously and developed muscle spasms so severe that he was immobilized. The soldier was hospitalized and underwent a battery of tests. The only abnormality found was a low concentration of magnesium in the blood serum (0.54 mmol/L vs. a normal range of 0.7 to 1.5 mmol/L). The soldier was given two intravenous infusions of magnesium sulfate in a saline solution. His pain lessened significantly within 48 hours and was gone after four days. The second case involved an 81-year-old woman who was hospitalized with abdominal cramps so severe that even injections of Demerol and morphine could not subdue the pain. Laboratory tests showed a significant magnesium deficiency (serum level was 0.50 mmol/L). The patient was given a slow intravenous infusion of five grams of magnesium sulfate in a 2000 ml N saline solution over a 24-hour period. She was completely pain-free by the third day and was discharged after another week “never feeling better for years”. The doctors conclude that diuretic therapy (with furosemide) was almost certainly the cause of this latter case of muscle cramps. They also recommend that physicians do a magnesium level check whenever patients complain of muscle cramps, muscle weakness or neuromuscular dysfunction. Oral supplements have also been found effective in treating muscle cramps with the preferred form being magnesium glucoheptonate or magnesium gluconate.
Bilbey, Douglas L.J. and Prabhakaran, Victor M. Muscle cramps and magnesium deficiency: case reports. Canadian Family Physician, Vol. 42, July 1996, pp. 1348-51