magnesium aspartate dihydrate: clinical use

Prescribing considerations

• Confirm the clinical reason for replacement and consider causes of magnesium loss.
• Assess renal function and interacting medicines before prescribing.
• Check for associated hypocalcaemia and hypokalaemia and correct them if confirmed.
• Oral magnesium preparations vary in bioavailability; review tolerance and therapeutic effect when switching products.
• The powder contains sucrose, relevant to diabetes, dental health and hereditary sugar-intolerance disorders.

Contraindications and cautions

• Hypersensitivity to magnesium aspartate dihydrate or an excipient.
• Severe renal impairment.
• Bradycardia or cardiac-conduction disorder.
• Fructose intolerance, glucose-galactose malabsorption or sucrase-isomaltase insufficiency because the product contains sucrose.

Monitoring

• Serum magnesium, especially in children, renal impairment, prolonged treatment or where magnesium-lowering medicines are used.
• Renal function and clinical features of magnesium accumulation.
• Calcium and potassium where magnesium deficiency is confirmed.
• Gastrointestinal tolerability and unexplained fatigue.

Clinical pharmacology

Magnesium acts as an enzyme cofactor and contributes to electrolyte homeostasis, membrane stability, neuromuscular transmission and cardiac contractility. Oral absorption is incomplete and increases when magnesium status is low; absorbed magnesium is eliminated mainly through the kidneys.

Formulation and product differences

• Powder for oral solution with a peach/apricot flavour.
• Contains sucrose and is essentially sodium-free.
• Bioavailability and tolerability may differ from other oral magnesium salts, so products should not be assumed interchangeable.
• Can be administered through an appropriate gastric, duodenal or nasal feeding tube after reconstitution.

Oral solution

Route: Oral

Strengths: 243 mg