Magnesium Flashcards
What is the normal range for magnesium?
1.5-2.4 mEq/L
Low Magnesium is associated with low ______
K+
Is Magnesium usually stored inside the cell or outside the cell?
inside the cell (intracellular cation)
Magnesium is a cofactor for many enzymatic reactions, pumps/channels that carry which electrolytes?
K+ and Ca2+
Where is magnesium primarily absorbed?
in the jejunum and ileum
How is magnesium eliminated?
in the kidneys
What is the renal threshold for magnesium excretion?
1.3-1.7 mEq/L (range at which kidney can excrete Mg2+)
What are some causes of hypomagnesemia?
Malnutrition
EtOH abuse
NG suction, laxatives, diarrhea
Malabsorption syndrome, small bowel resection
Drugs: cisplatin, aminoglycosides, cyclosporine, amph B, loop, thiazide diuretics
What is the clinical presentation of hypomagnesemia?
muscle weakness, cramps agitation, confusion tremor, seizures EKG changes • increased PR interval • prolonged QRS • increased QT interval metabolic alkalosis refractory correction of K+ (when you keep giving K+ but it doesn't increase)
How do you treat mild hypomagnesemia that has no symptoms?
oral preps
How do you treat moderate to severe hypomagnesemia that has symptoms?
IV magnesium sulfate
What are other uses for IV Mag?
it can also treat torsades de pointes or to prevent eclampsia in pregnancy
Any administration considerations to worry about with IV magnesium?
you must dilute the Mg2+ to less than 20% before giving to avoid severe hypotension
Oral Mg2+ soften used as a laxative so a side effect may be ___________.
diarrhea
What is the normal dose of Mg2+ given?
2-4 g
