Magnesium - Electrolytes

Magnesium *

·        Stored 65% in bone, 35% in cells

·        Concentration generally follows Ca and K

·        Excess:

o  Usually in renal failure Þ treat renal failure not magnesium

o  Symptoms: neuromuscular depression ® ¯BP ® CNS depression

·        Deficiency:

o  Causes: severe diarrhoea, ketoacidosis, alcohol, TPN, with ¯Ca or ¯K (especially diuretics)

o  Symptoms: tetany (same as ¯Ca, ¯K gives weakness), fits, arrhythmia

·        Treatment: Mg salts either po or iv