From the Guidelines
Hypomagnesemia is primarily caused by decreased absorption or increased loss of magnesium from either the kidneys or intestines, with factors such as malnourishment, certain medications, and alterations in thyroid hormone function also playing a role. According to the most recent and highest quality study 1, hypomagnesemia can be caused by various factors, including inadequate dietary intake, increased gastrointestinal losses, and increased renal losses.
Causes of Hypomagnesemia
Some of the common causes of hypomagnesemia include:
- Inadequate dietary intake, such as malnutrition, alcoholism, and prolonged fasting
- Increased gastrointestinal losses, which can occur with conditions like chronic diarrhea, malabsorption syndromes, inflammatory bowel disease, celiac disease, and after bariatric surgery
- Increased renal losses, which can result from genetic disorders like Gitelman syndrome and Bartter syndrome, as well as the use of certain medications like diuretics and proton pump inhibitors
- Medications, particularly diuretics (especially loop and thiazide diuretics), proton pump inhibitors, certain antibiotics (aminoglycosides, amphotericin B), immunosuppressants (cyclosporine, tacrolimus), and some chemotherapy agents (cisplatin)
- Endocrine disorders, such as hyperaldosteronism, hyperthyroidism, and hyperparathyroidism
- Other causes, including diabetic ketoacidosis, acute pancreatitis, severe burns, and excessive sweating
Treatment and Prevention
Treatment of hypomagnesemia involves addressing the underlying cause and providing magnesium supplementation, either orally (magnesium oxide, citrate, or glycinate) for mild cases or intravenously (magnesium sulfate) for severe deficiency or when oral supplementation isn't feasible, as noted in 1 and 1. It is essential to monitor plasma potassium levels and supplement as required, especially in patients with inflammatory bowel disease, as mentioned in 1. Additionally, magnesium is crucial for numerous physiological processes, including neuromuscular function, enzyme reactions, and maintaining normal cardiac rhythm, highlighting the importance of prompt treatment and prevention of hypomagnesemia.
From the FDA Drug Label
As a nutritional adjunct in hyperalimentation, the precise mechanism of action for magnesium is uncertain. Early symptoms of hypomagnesemia (less than 1. 5 mEq/L) may develop as early as three to four days or within weeks. While there are large stores of magnesium present intracellularly and in the bones of adults, these stores often are not mobilized sufficiently to maintain plasma levels.
The causes of hypomagnesemia (low or depleted magnesium) are not directly stated in the provided drug label. However, it can be inferred that factors affecting the mobilization of magnesium stores, nutritional deficiencies, or increased excretion may contribute to its development.
- Key factors that may lead to hypomagnesemia include:
- Inadequate nutritional intake
- Impaired mobilization of magnesium stores
- Increased renal excretion The label does not provide explicit information on the causes of hypomagnesemia, only its effects and treatment 2.
From the Research
Causes of Low or Depleted Magnesium
- Low dietary intake of magnesium, with intakes of less than 250 mg/day, can lead to hypomagnesemia 3
- Certain medical conditions, such as type 2 diabetes, can increase the risk of magnesium depletion, with low Mg intake and increased Mg urinary loss being key mechanisms 4
- Proton pump inhibitors (PPIs) have been reported to cause hypomagnesemia, although the exact mechanism is still unknown, with possible factors including reduced Mg2+ solubility in the intestinal lumen and changes in the expression and activity of key transporter proteins 5
- However, some studies have found no association between PPI use and hypomagnesemia, regardless of dose or concomitant diuretic use, suggesting that routine screening of serum magnesium in PPI patients may be unnecessary 6
Factors Contributing to Magnesium Depletion
- Insulin resistance and type 2 diabetes can lead to defective tyrosine-kinase activity, postreceptorial impairment in insulin action, and worsening of insulin resistance in diabetic patients 4
- Increased Mg urinary loss can contribute to magnesium depletion, particularly in patients with type 2 diabetes 4
- Gut microbiome changes caused by PPI use may also contribute to the development of PPI-induced hypomagnesemia 5