calcium carbonate + magnesium carbonate, heavy: clinical use

Prescribing considerations

• Confirm that recurrent or persistent dyspepsia is not being managed inappropriately by prolonged self-treatment.
• Assess renal function, stone history, calcium intake and medicines with absorption interactions.
• Avoid concurrent excessive milk or dairy consumption.
• Review excipients against diabetes, dental health and hereditary carbohydrate-intolerance requirements.

Contraindications and cautions

• Hypersensitivity to an active ingredient or excipient
• Hypercalcaemia or a condition causing hypercalcaemia
• Hypercalciuria
• Calcium-containing nephrolithiasis
• Severe renal insufficiency
• Hypophosphataemia

Monitoring

• In mild-to-moderate renal impairment, monitor plasma calcium, phosphate and magnesium if treatment is considered.
• Monitor serum calcium when used with a thiazide diuretic.
• Investigate persistent, recurrent, worsening or alarm symptoms rather than continuing antacid treatment.

Clinical pharmacology

Calcium carbonate and magnesium carbonate neutralise gastric hydrochloric acid locally. Limited quantities are absorbed and normally eliminated by the kidneys; renal impairment increases the risk of accumulation, alkalosis and milk-alkali syndrome.

Formulation and product differences

• Both selected products are chewable antacid tablets containing the same active ingredients.
• Spearmint contains glucose and sucrose and may be harmful to teeth; check suitability in relevant sugar-intolerance disorders.
• Sugar Free replaces sugars with sweetening excipients; check current product information where polyol intolerance or hereditary fructose intolerance is relevant.
• Excipients and flavourings differ, so hypersensitivity and intolerance checks must be product-specific.