Rennie^® (Tablets) Instructions for Use

ATC Code

A02AX (Antacids in combination with other agents)

Active Substances

Calcium carbonate (Ph.Eur.)

Magnesium carbonate (Ph.Eur.)

Clinical-Pharmacological Group

Antacid drug

Pharmacotherapeutic Group

Antacid agent

Pharmacological Action

A locally acting antacid drug. Each Rennie^® tablet contains antacid substances – Calcium Carbonate and magnesium carbonate, which provide rapid and prolonged neutralization of excess hydrochloric acid in gastric juice, thereby exerting a protective effect on the gastric mucosa.

The rapid achievement of a positive effect is due to the good solubility of the tablets and the high content of calcium carbonate.

Calcium Carbonate has a rapid, long-lasting, and strong neutralizing effect. This effect is enhanced in the presence of magnesium carbonate, which also has a strong neutralizing effect.

In vitro acid neutralization studies (artificial stomach model) showed that Rennie^® increases gastric pH from 1.5-2 to 3 within 40 seconds and can reach a pH value of 4 in 1 minute 13 seconds. The maximum pH level achieved in the model test was 5.24.

Pharmacokinetics

Absorption

As a result of the interaction of Rennie^® with gastric juice, soluble calcium and magnesium salts are formed in the stomach. The degree of absorption of calcium and magnesium from these compounds depends on the dose of the drug. Maximum absorption is 10% for calcium and 15-20% for magnesium.

Excretion

A small amount of absorbed calcium and magnesium is excreted by the kidneys. In the intestine, insoluble compounds are formed from the soluble salts, which are excreted in the feces.

Pharmacokinetics in special clinical cases

In case of impaired renal function, the plasma concentration of calcium and magnesium may increase.

Indications

• Symptoms associated with increased acidity of gastric juice and reflux esophagitis: heartburn, sour belching, occasional stomach pain, feeling of fullness or heaviness in the epigastric region, dyspepsia (including those caused by dietary errors, medication intake, excessive consumption of alcohol, coffee, nicotine);
• Dyspepsia of pregnancy.

ICD codes

Dosage Regimen

Tablets

The drug is taken orally.

For adults and children over 12 years of age, when symptoms appear, 1-2 tablets should be chewed (or held in the mouth until completely dissolved). If necessary, the dose can be repeated after 2 hours. The maximum daily dose is 11 tablets.

Without a doctor’s instruction, the maximum daily dose of calcium carbonate, equal to 8 g (corresponding to 11 tablets of Rennie^®), should not be exceeded, or the drug should not be used at the maximum daily dose continuously for more than 2 weeks.

Adverse Reactions

The listed adverse drug reactions are based on spontaneous reports, so their classification according to the CIOMS III frequency categories is not applicable.

Immune system disorders: very rarely – hypersensitivity reactions (rash, urticaria, pruritus, angioedema, dyspnea, anaphylaxis).

Metabolism and nutrition disorders: long-term use of the drug in high doses may lead to hypermagnesemia or hypercalcemia and alkalosis, especially in patients with renal insufficiency.

Gastrointestinal disorders: nausea, vomiting, stomach discomfort, constipation and diarrhea may occur in predisposed patients.

Musculoskeletal and connective tissue disorders: possible – muscle weakness.

Drug overdose may lead to the formation of milk-alkali syndrome, including the following manifestations.

Gastrointestinal disorders: loss of taste;

General disorders and administration site conditions: calcinosis and asthenia;

Nervous system disorders: headaches.

Renal and urinary disorders: azotemia.

Contraindications

• Hypersensitivity to the components of the drug;
• Hypercalcemia (and/or conditions leading to hypercalcemia);
• Nephrolithiasis (urolithiasis);
• Severe renal failure;
• Hypophosphatemia;
• Sucrase/isomaltase deficiency, fructose intolerance, glucose-galactose malabsorption (for chewable tablets);
• Children under 12 years of age.

With caution pregnancy; period of breastfeeding; age under 18 years.

Use in Pregnancy and Lactation

When used in recommended doses, the drug does not pose a danger to the fetus or child.

To prevent excessive calcium intake, pregnant women should avoid concomitant excessive consumption of milk and dairy products.

Use in Renal Impairment

The drug is contraindicated in severe renal failure, nephrocalcinosis.

When prescribing the drug to patients with impaired renal function, the serum concentrations of magnesium, phosphorus and calcium should be regularly monitored.

Patients with impaired renal function are not recommended to take the drug for a long time in high doses.

The use of Rennie^® in high doses may increase the risk of kidney stone formation.

Pediatric Use

Contraindicated for use in children under 12 years of age.

Special Precautions

Prolonged use of the drug and exceeding the indicated dose should be avoided. If symptoms persist or only partially disappear, it is necessary to consult a doctor.

When prescribing the drug to patients with impaired renal function, the serum concentrations of magnesium, phosphorus and calcium should be regularly monitored.

Patients with impaired renal function are not recommended to take the drug for a long time in high doses.

The use of Rennie^® in high doses may increase the risk of kidney stone formation.

Long-term use of the drug in high doses may lead to adverse reactions such as hypercalcemia, hypermagnesemia and milk-alkali syndrome, especially in patients with renal insufficiency. These drugs should not be taken with large amounts of milk or dairy products. Prolonged use of these drugs with the specified products increases the risk of kidney stone formation.

Instructions for patients with diabetes mellitus

Each Rennie^® chewable tablet (menthol)/chewable tablet (orange) contains 475 mg of sucrose.

1 Rennie^® sugar-free (mint) tablet contains 400 mg of sorbitol and can be prescribed to patients with diabetes mellitus.

Effect on ability to drive vehicles and machinery

No effect.

Overdose

Symptoms long-term use of the drug in high doses in patients with impaired renal function may lead to renal failure, hypermagnesemia, hypercalcemia, alkalosis, which are manifested by nausea, vomiting, muscle weakness.

Treatment administration of the drug should be discontinued and adequate fluid intake should be ensured. In serious cases of overdose (e.g., milk-alkali syndrome), a doctor should be consulted, as other rehydration measures (e.g., infusions) may be required.

Drug Interactions

Changes in gastric juice acidity caused by antacid intake may lead to a decrease in the rate and extent of absorption of other drugs taken simultaneously, therefore medicinal products should be taken 1-2 hours before or after taking antacids.

With simultaneous use, antacids reduce the absorption of tetracycline antibiotics, fluoroquinolones, cardiac glycosides (digoxin), bisphosphonates, dolutegravir, levothyroxine, eltrombopag, iron preparations, fluorides, phosphates.

With simultaneous use with thiazide diuretics, serum calcium concentration should be regularly monitored.

Storage Conditions

The drug should be stored out of the reach of children at a temperature not exceeding 25°C (77°F).

Shelf Life

Shelf life: for chewable tablets (menthol) – 5 years; for chewable tablets (orange), sugar-free chewable tablets (mint) – 3 years. Do not use after the expiration date.

Dispensing Status

The drug is available without a prescription.

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.