Plasma levels poorly reflect intracellular or whole body stores, 65% of which is in bone and 35% in cells. The ionised fraction is approximately 50% of the total level.

High magnesium levels are seen with renal failure and excessive administration; this rarely requires treatment unless serious cardiac conduction problems or neurological complications (respiratory paralysis, coma) intervene.

Low levels occur following severe diarrhoea, diuretic therapy, alcohol abuse, and accompany hypocalcaemia.

Magnesium is used therapeutically for a number of conditions including ventricular and supraventricular arrhythmias, eclampsia, seizures, asthma and after myocardial infarction. Supranormal plasma levels of 1.5-2.0mmol/l are often sought.

0 0

Post a comment