Magnesium Chloride is available as an injection and oral formulation for the treatment and prevention of magnesium deficiency. It is also used as an oral dietary supplement.

Magnesium chloride Uses:

• It is used for the treatment and prevention of hypomagnesemia in patients who are deficient or are at risk of magnesium deficiency.
• As a dietary magnesium supplement.

Magnesium Chloride Dose in Adults:

Note: Serum magnesium is a poor reflection of the body magnesium as most of the magnesium is intracellular. Furthermore, the serum levels may be transiently normal or high after a few hours of the dose. It is best to aim for consistently high normal serum levels in patients with normal kidney functions for efficient repletion.

Magnesium Chloride Dose in the prevention of Hypomagnesemia (parenteral nutrition supplementation):

• IV (elemental magnesium):
  • 8 to 20 mEq/day

Magnesium Chloride Dose as Dietary supplement:

• Oral (Mag 64, Mag-Delay, Slow-Mag):
  • 2 tablets once a day.

Magnesium Chloride Dose in Childrens:

Note: Dosing presented in mg and mEq, verify dosing units; 1,000 mg of magnesium chloride = 119.7 mg elemental magnesium = 9.85 mEq elemental magnesium = 4.93 mmol elemental magnesium; Since the majority of magnesium is intracellular, the serum magnesium is poor reflection of repletional status. The serum concentrations may be transiently normal after a dose is given for a few hours; therefore, aim for high normal serum levels in patients with normal renal functions for efficient repletion.

Magnesium Chloride Dose in the treatment of Hypomagnesemia:

• Infants, Children, and Adolescents:

  • Dose expressed as elemental magnesium:

    • IV:
      • 2.5 to 5 mg/kg/dose every six hours for 2 to 3 doses;
      • The dosing is based on experience with magnesium sulfate salt which is preferred.
    • Oral:
      • 10 to 20 mg/kg/dose up to four times a day.

Note: Patients with severe deficiency or those who require higher doses for rapid correction may need intravenous magnesium as oral formulations may result in diarrhea.

Magnesium Chloride Dose as maintenance requirement of Parenteral nutrition:

Note: Dose expressed as elemental magnesium:

• Infants and Children ≤50 kg:

  • 3 to 0.5 mEq/kg/day intravenously

• Children >50 kg and Adolescents:

  • 10 to 30 mEq/day IV

Pregnancy Risk Factor C

• Animal studies have not yet been done. It can cross the placental boundary. It can cross the placental barrier.

Use during lactation:

• It can be found in breast milk. It is found in breast milk.
• The concentrations in lactating and nonlactating females are identical.

Dose in Kidney Disease:

• The manufacturer recommends against its use in patients with renal impairment.
• It is contraindicated in patients with kidney disease.

Dose in Liver disease:

There are no dosage adjustments provided in the manufacturer’s labeling.

Side effects of Magnesium Chloride:

• Gastrointestinal:

  • Diarrhea with excessive oral doses
  • Nauses
  • vomiting
  • abdominal pain

• Other:

  • Weakness
  • lethargy
  • cardiac arrhythmias
  • hypotension

Contraindications to Magnesium chloride:

• Hypersensitivity to any ingredient of the formulation
• Renal impairment
• Myocardial disease
• Coma

Warnings and precautions

• Neuromuscular disease

  • Patients suffering from neuromuscular diseases such as myasthenia gravis or other similar conditions should be cautious.

• Renal impairment

  • Patients with kidney disease may be more susceptible to magnesium accumulation. These patients should be cautious when using magnesium.

Magnesium chloride: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use

Monitoring parameters:

IV:

• Monitor ECG, vital signs, and deep tendon reflexes especially when rapid administration is required;
• Monitor magnesium, calcium, and potassium levels;
• Monitor kidney function during administration

Oral:

• Monitor kidney function;
• Magnesium levels;
• Bowel movements

How to administer Magnesium Chloride?

Oral formulations:

• It should be administered after meals, at least two hours apart from other medications.

IV formulations:

• It should be administered slowly as an intravenous infusion over a minimum period of 30 minutes.

Mechanism of action of Magnesium chloride:

• Magnesium is a cofactor of many enzymes. 
• Magnesium is required for proper functioning of around 300 enzymes.
• It is a cofactor of enzymes involved in carbohydrate, protein, and lipid synthesis. 
• It reduces serum cholesterol and acts on lipoprotein lipases. 
• It can also act on the sodium/potassium ATPase, resulting in the polarization and reorganization of neurons.

Absorption:

• Orally administered drugs are absorbed in inverse proportion to their amount.
• Under controlled dietary conditions, 40% to 60% can be absorbed
• Higher doses of the drug can result in a 15% to 36% absorption.

Distribution:

• Half to 60% of magnesium goes to bones, and 1% to 2% to extracellular fluid.

Protein binding:

• 30% of the drug is bound to albumin.

Excretion:

• It is excreted in urine (as magnesium)

International Brand Names of Magnesium chloride:

• Chloromag
• Mag-SR Plus Calcium
• Magdelay
• Nu-Mag
• Slow Magnesium/Calcium
• Slow-Mag

Magnesium chloride Brand Names in Pakistan: