Magnesium citrate and Magnesium oxide are examples of magnesium supplements. They are used for a lot of things. Both magnesium oxide and magnesium citrate are used as laxatives, this means they are substances that have the effect of moving the bowels, or aiding digestion and preventing constipation. Both magnesium oxide and magnesium citrate are used before surgery to remove stool in the intestine.
Although both substances are used for a lot of things, magnesium citrate differs from magnesium oxide in some ways. First of all, in terms of their availability, magnesium oxide can easily be found because they are present in large proportion compared to magnesium citrate. In terms of solubility, magnesium citrate has high solubility; that is, it is more soluble in water than magnesium oxide. Another difference is their molecular formula, the molecular formula of magnesium oxide is MgO, while the molecular formula of magnesium citrate is C12H10Mg3O14.