The effect of oral magnesium chloride therapy on the QTc and QUc intervals of the electrocardiogram

S Afr Med J. 1978 Apr 15;53(15):591-3.


The effect of magnesium, given orally as enteric-coated magnesium chloride tablets, on the ECG of 25 randomly selected patients was investigated. Each patient, who served as his own control, was given 4--6 tablets, each containing 0,5 g MgCl26H2O, at night for periods varying from 6 weeks to 2 years. Findings included (i) a statistically significant decrease in OTc and QUc intervals; (ii) a progressive shortening of QTc and QUc intervals with continuing therapy; (iii) reversion to normal of ECG abnormalities, especially of ST segments and T waves.

MeSH terms

  • Administration, Oral
  • Electrocardiography*
  • Female
  • Heart / drug effects
  • Heart / physiology
  • Humans
  • Magnesium / administration & dosage*
  • Magnesium / pharmacology
  • Male
  • Myocardium / metabolism


  • Magnesium