Hypomagnesemia

This morning we reviewed a case of severe hypomagnesemia .

Patients often present with generalized weakness and non-specific complaints, but VENTRICULAR ARRYTHMIA and neurologic finings such as delirium and coma can also occur.

ETIOLOGY
- GI losses: diarrhea
- Renal losses: renal failure or renal magnesium wasting due to drugs such as diuretics, aminoglycosides, or cisplatin, or rare genetic causes such as Gitleman's disease
- Alcohol: causes renal tubular dysfunction and urinary loss of Mg.
- Decrease PO intake

**Think of Magnesium depletion in refractory hypokalemia or unexplained hypocalcemia.

MANAGEMENT:
Route depends on severity and renal function

If hypomagnesemic-hypokalemic ventricular arrhythmias: give 50 meq of IV magnesium slowly over 8 to 24 hours and repeated as necessary to maintain the plasma magnesium concentration above 0.4 mmol/L or 0.8 meq/L.

Oral replacement is adequate for asymptomatic patient.

Treat the underlying disease.