Treatment of Magnesium Deficiency
The most effective treatment for magnesium deficiency is oral magnesium supplementation, typically with magnesium oxide at a dose of 12-24 mmol daily, preferably taken at night when intestinal transit is slowest to maximize absorption. 1
Initial Assessment and Treatment Options
- Magnesium deficiency can cause symptoms including abdominal cramps, impaired healing, fatigue, and bone pain 1
- Serum magnesium is not always an accurate measurement of total body magnesium status, as less than 1% of magnesium stores are in the blood, with the remainder in bone, soft tissue, and muscle 1, 2
- First step in treatment is to correct any underlying water and sodium depletion to address secondary hyperaldosteronism 1
Oral Supplementation
- Magnesium oxide is commonly recommended because it contains more elemental magnesium than other salts 1
- Typical dosing is 12-24 mmol daily (approximately 4 mmol/160 mg per capsule) 1
- Taking magnesium supplements at night may improve absorption due to slower intestinal transit 1
- Be aware that oral magnesium supplements may worsen diarrhea in some patients 1
Additional Treatment Strategies
- If oral supplements don't normalize magnesium levels, consider oral 1-alpha hydroxy-cholecalciferol in gradually increasing doses (0.25-9.00 mg daily) to improve magnesium balance 1
- Regular monitoring of serum calcium is necessary when using vitamin D supplements to avoid hypercalcaemia 1
- Consider reducing excess dietary lipid, which may improve magnesium status 1
- For patients with severe hypomagnesemia not responding to oral therapy, intravenous magnesium may be necessary 1, 3
Intravenous Magnesium for Severe Deficiency
- For severe hypomagnesemia, IV magnesium sulfate may be required 3
- Standard dosing for mild deficiency is 1g (8.12 mEq) injected IM every six hours for four doses 3
- For severe hypomagnesemia, up to 250 mg/kg body weight may be given IM within a four-hour period, or 5g can be added to 1L of IV fluid for slow infusion over three hours 3
- Monitor serum magnesium levels during and after infusion to avoid toxicity 4
Dietary Sources of Magnesium
- Increase consumption of magnesium-rich foods including green leafy vegetables, nuts, legumes, and whole grains 5
- A varied diet that meets energy and nutrient requirements is recommended 1
- Avoid non-evidence-based exclusion diets which can lead to limited diet quality and nutrient deficiency 1
Special Considerations
- Patients with renal insufficiency require careful dosage adjustment of magnesium supplements 3
- Certain medications, particularly loop and thiazide diuretics, can increase magnesium excretion and worsen deficiency 6
- Patients with gastrointestinal disorders like short bowel syndrome or IBD have higher risk of magnesium deficiency due to increased losses 1
Remember that magnesium is essential for over 300 enzymatic reactions in the body, and deficiency has been linked to many diseases including cardiovascular disorders, metabolic syndrome, and poor health outcomes 7, 2.