Magnesium Sulfate In Patients Research Articles

Pregnancy associated with Friedreich ataxia

The pregnancy of a woman with Friedreich ataxia was complicated by the onset of preterm labor and preeclampsia. Administration of magnesium sulfate (MgSO4.7H2O) in the usual intravenous dosage resulted in the dramatic development of profound motor weakness and respiratory distress. Magnesium acts to antagonize the action of acetylcholine at the motor end plate of the neuromuscular junction and may operate synergistically with underlying neuromuscular disorders. Therefore, the use of magnesium sulfate in patients with Friedreich ataxia and other similar neurodegenerative diseases is contraindicated.

Pregnancy associated with friedreich ataxia

The pregnancy of a woman with Friedreich ataxia was complicated by the onset of preterm labor and preeclampsia. Administration of magnesium sulfate (MgSO4.7H2O) in the usual intravenous dosage resulted in the dramatic development of profound motor weakness and respiratory distress. Magnesium acts to antagonize the action of acetylcholine at the motor end plate of the neuromuscular junction and may operate synergistically with underlying neuromuscular disorders. Therefore, the use of magnesium sulfate in patients with Friedreich ataxia and other similar neurodegenerative diseases is contraindicated.

Suppression of exercise-induced angina by magnesium sulfate in patients with variant angina

The effects of intravenous magnesium on exercise-induced angina were examined in 15 patients with variant angina and in 13 patients with stable effort angina and were compared with those of placebo. Symptom-limited bicycle exercise and thallium-201 myocardial scintigraphy were performed after intravenous administration of 0.27 mmol/ kg body weight of magnesium sulfate and after placebo on different days. In all patients, serum magnesium levels after administration of magnesium sulfate were about twofold higher than levels after placebo.Exercise-induced angina associated with transient ST segment elevation occurred in 11 patients with variant angina receiving placebo and in only 2 of these patients receiving magnesium (p < 0.005). On the other hand, exercise-induced angina was not suppressed by magnesium in any patient with stable effort angina. In these patients there was no significant difference in exercise duration after administration of placebo versus after administration of magnesium. The size of the perfusion defect as measured by thallium-201 scintigraphy was significantly less in patients with variant angina receiving magnesium than that in those receiving placebo (p < 0.001), whereas it was not significantly different in patients with stable effort angina receiving placebo versus magnesium.In conclusion, exercise-induced angina is suppressed by intravenous magnesium in patients with variant angina but not in patients with stable effort angina. This beneficial effect of magnesium in patients with variant angina is most likely due to improvement of regional myocardial blood flow by suppression of coronary artery spasm.

Influence of magnesium on drug-induced contractions and ion content in rabbit aorta.

Influence of magnesium on drug-induced contractions and ion content in rabbit aorta.

Effects of magnesium sulfate on renal function, electrolyte excretion and clearance of magnesium.

The constant intravenous infusion of magnesium sulfate in patients with chronic renal disease produced a significant decrease in renal plasma flow, no change in glomerular filtration rate and no alteration in urinary excretion of sodium, chloride and potassium. Normal men had shown a similar decline in renal plasma flow but also a decrease in glomerular filtration rate, an increase in urinary excretion of sodium and chloride and a decrease in urinary excretion of potassium. The serum concentrations of these electrolytes were not altered in either group. The values for clearance of magnesium in this study were below those required to implicate tubular excretion of this ion. Submitted on October 15, 1956