Clinical Case 82: Answers and Summary

Which oral magnesium preparation has the highest amount of elemental magnesium content?

Milk of magnesia

  4 (11%)

 

Magnesium citrate

  7 (19%)

 

Magnesium oxide

  13 (36%)

 

Magnesium chloride

  5 (13%)

 

Magnesium lactate

  3 (8%)

 

Magnesium carbonate

  4 (11%)

 

Magnesium oxide  has the highest ( 61%) elemental magnesium; 242mg in a 400mg tablet

Milk of Magnesia Or Magnesium Hydroxide  has the second highest ( 42%).

Mg Carbonate has 24%

Mg Citrate has 16% elemental Mg

MgCl has 12%

Mg lactate has 10%

Other ones not listed are Mg gluconate that has 5% elemental Mg, Mg aspartate HCl that has 10%
Mg glycerophosphate that has 10% as well.

Check out a nice review article in AJKD by Ayuk and Gittoes on management of hypomagnesemia.