Pharmacy Guide

Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.

Pharmacy Guide

Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.

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Rennie Sugar Free

⚠ This medicine appears to have been discontinued

The electronic medicines compendium (emc) no longer publishes a Summary of Product Characteristics for this product, which usually means it is no longer marketed in the UK. The patient leaflet below is kept for reference, but the product may not be available.

If you were prescribed this medicine, other products containing Calcium carbonate, Magnesium carbonate, heavy may still be available. Do not stop your treatment — ask your pharmacist or GP what to use instead.

Active substance: Calcium carbonate, Magnesium carbonate, heavy

Equivalent medicines (same active substance, strength and form)

Source: electronic medicines compendium (emc)
Official leaflet: Read the PIL on emc

What it is and what it is used for

FOR Rennie Sugar Free fast-acting tablets get to work within minutes to provide effective relief from heartburn, indigestion and acid reflux. Each tablet contains two antacids – calcium carbonate and magnesium carbonate – that work quickly and powerfully to neutralise excess acid in the stomach.

What you need to know before you take it

E RENNIE® SUGAR FREE Do not take Rennie Sugar Free if you:

  • Have severe kidney disease.
  • Have high calcium in the urine or kidney stones.
  • Have high calcium or low phosphate levels in the blood.
  • Are allergic (hypersensitive) to any of the ingredients (listed in Section 6).

Reporting of side effects: If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.

Warnings and precautions: Do not exceed the stated dose. Rennie Sugar Free should not be used for more than 14 days without consulting a doctor. Please consult your doctor or pharmacist if you have mild or moderate kidney problems as regular blood tests should be carried out. 92753500

Other medicines and Rennie Sugar Free:

  • Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained without a prescription.
  • If you are taking any of the following medicines speak to your doctor or pharmacist before taking Rennie Sugar Free because it can affect how these medicines work.
  • Tetracyclines and quinolones (antibiotics)
  • Bisphosphonates (used for the treatment of osteoporosis)
  • Dolutegravir (an anti-retroviral medicine used for the treatment of HIV infection)
  • Levothyroxine (a thyroid hormone)
  • Eltrombopag (used to increase the number of platelets)
  • Digoxin (used for some heart conditions)
  • Thiazide diuretics (water tablets to treat fluid retention and high blood pressure)
  • Fluorides (for preventing dental caries)
  • Phosphates (for clearing the bowel before a surgical procedure)
  • Iron supplements
  • To maximise the benefit of all medicines being used, take Rennie Sugar Free at least 4 hours before or after taking eltrombopag and 1 to 2 hours after taking any other medicines. Rennie Sugar Free with food and drink Avoid taking Rennie Sugar Free with large amounts of milk or dairy products. Pregnancy and breastfeeding: Rennie Sugar Free can be used during pregnancy and breastfeeding if taken as instructed. As Rennie Sugar Free provides a substantial amount of calcium in addition to dietary calcium intake, pregnant women should strictly limit their use of Rennie Sugar Free to the maximum recommended daily dose and avoid concomitant, excessive intake of milk (1 litre contains up to 1.2 g elemental calcium) and dairy products. Rennie Sugar Free contains isomalt and saccharin This medicine contains 500 mg isomalt in each tablet. If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicinal product.

Frequently asked questions about Rennie Sugar Free

What is the active substance in Rennie Sugar Free?

The active substance in Rennie Sugar Free is calcium carbonate, magnesium carbonate, heavy.

Are there equivalent medicines to Rennie Sugar Free?

Medicines with the same active substance, strength and form include: Rennie Peppermint, Rennie Spearmint. They are interchangeable only if your prescriber or pharmacist says so.

Where does this information come from?

This leaflet reproduces the patient information leaflet approved for Rennie Sugar Free, as published on the electronic medicines compendium (emc). The version printed inside your medicine’s packaging is the one that applies to you.

Can I get Rennie Sugar Free without a prescription?

Whether a medicine is available over the counter or on prescription only depends on its licence. Check the leaflet, or ask your pharmacist — they can tell you straight away.

About this leaflet

The text above reproduces the patient information leaflet approved for this medicine, restructured for easier reading.

Medical disclaimer: This page is for information only and does not replace advice from your doctor or pharmacist. Always read the leaflet supplied with your medicine. If you are unwell, call NHS 111; in an emergency, call 999.

Medicines with the same active substance: Calcium carbonate (45 medicines), Calcium carbonate, magnesium carbonate, heavy (3 medicines)
See every medicine containing this substance, or browse the full A–Z of active substances.
⚕For healthcare professionals — Summary of Product Characteristics (SmPC)Full SmPC: dosage, interactions, contraindications, warnings+
Technical information intended for healthcare professionals (doctors and pharmacists). The Summary of Product Characteristics (SmPC) is the official document approved by the MHRA/EMA. It does not replace the patient leaflet or a doctor’s advice.

4.1. Therapeutic indications

For the relief of indigestion, heartburn, nervous indigestion, hyperacidity, flatulence, upset stomach, dyspepsia, biliousness, gastritis, overindulgence in food and drink, indigestion during pregnancy.

4.2. Posology and method of administration

Posology:

Tablets to be taken orally, sucked or chewed.

Adults and Children over 12 years:

Two tablets to be sucked or chewed as a single dose, preferably to be taken one hour after meals and before going to bed but also in between in case of heartburn or gastric pain. A maximum daily dose of 8 g calcium carbonate, corresponding to 10 tablets a day, must not be exceeded.

Rennie Sugar Free is suitable for diabetics.

Children

Not recommended for children under 12 years.

As with all antacids, if symptoms persist despite 14 days of continuous therapy, diagnostic measures are strongly recommended in order to rule out a more serious disease.

4.3. Contraindications

Rennie should not be administered to patients with:

• Hypersensitivity to any of the ingredients of the product

• Hypercalcaemia and/or conditions resulting in hypercalcaemia

• Nephrolithiasis due to calculi containing calcium deposits

• Severe renal insufficiency

• Hypophosphataemia

4.4. Special warnings and precautions for use

• Prolonged use should be avoided.

• The stated dose should not be exceeded. If, after 14 days of treatment, symptoms persist or only partly disappear the patient should consult a doctor.

• Caution should be exercised in patients with mild to moderate impairment of renal function (see section 4.3 – contraindication in severe renal insufficiency). If Rennie is used in such patients, plasma calcium, phosphate and magnesium levels should be regularly monitored.

• Long term uses at high doses can result in undesirable effects such as hypercalcaemia, hypermagnesaemia and milk-alkali syndrome, especially in patients with renal insufficiency.

• Rennie should not be used in patients with hypercalciuria (see also section 4.3). Prolonged use increases the risk of formation of renal calculi.

• This product should not be taken with large amounts of milk or dairy products.

• Patients with rare hereditary problems of fructose intolerance should not take this medicine.

4.5. Interaction with other medicinal products and other forms of interaction

Changes in gastric acidity, such as that caused by the ingestion of antacids, can affect the rate and degree to which some concurrently administered medicines are absorbed.

• It has been shown that antacids which contain calcium or magnesium may form complexes with certain substances e.g. antibiotics (such as tetracyclines and quinolones), and cardiac glycosides (e.g. digoxin), bisphosphonates, dolutegravir, levothyroxine, and eltrombopag, resulting in decreased absorption. This should be borne in mind when concomitant administration is considered.

• Calcium salts reduce the absorption of fluorides and iron-containing products, and calcium salts and magnesium salts can hinder the absorption of phosphates.

• Thiazide diuretics reduce the urinary excretion of calcium. Due to an increased risk of hypercalcaemia, serum calcium should be regularly monitored during concomitant use of thiazide diuretics.

Therefore it is preferable to take the antacid separately from other drugs, allowing at least 4 hours before or after taking eltrombopag and a 1-2 hour interval for all other drugs.

4.6. Fertility, pregnancy and lactation

Pregnancy

Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity.

No increased risks of congenital defects have been observed after the use of this product during pregnancy.

This medicine can be used during pregnancy if taken as instructed.

The maximum recommended daily dose should not be exceeded and should not be taken for more than 2 weeks. If symptoms persist or only partly disappear after 2 weeks, medical advice should be sought.

In order to prevent calcium overload, pregnant women should avoid concomitant excessive intake of milk and dairy products (1 litre of milk contains up to 1.2 g elemental calcium).

Breastfeeding

Calcium and magnesium are excreted in human milk, but at therapeutic doses of the product no effects on the breastfed newborns/infants are anticipated.

This medicine can be used during breastfeeding.

Fertility

There is no known evidence suggestive that at recommended dose this medicine has adverse effects on human fertility.

4.7. Effects on ability to drive and use machines

No effects on ability to drive and use machines have been observed.

4.8. Undesirable effects

The listed adverse drug reactions are based on spontaneous reports, thus an organisation according to CIOMS III categories of frequency is not possible.

Immune System Disorders:

Hypersensitivity reactions have very rarely been reported. Clinical symptoms may include rash, urticaria, pruritus, angioedema, difficulty in breathing and anaphylaxis.

Metabolism and Nutrition Disorders:

Especially in patients with impaired renal function, prolonged use of high doses can result in hypermagnesaemia or hypercalcaemia and alkalosis which may give rise to gastric symptoms and muscular weakness (see below).

Gastrointestinal Disorders:

Nausea, vomiting, stomach discomfort, constipation and diarrhoea may occur.

Musculoskeletal and Connective Tissue

Disorders: Muscular weakness may occur.

Undesirable effects occurring in the context of milk-alkali syndrome (see section 4.9)

Gastrointestinal Disorders:

Ageusia may occur in the context of milk-alkali syndrome.

General Disorders and Administration Site Conditions:

Calcinosis and asthenia may occur in the context of milk-alkali syndrome.

Nervous System Disorders:

Headache may occur in the context of milk-alkali syndrome.

Renal and Urinary Disorders:

Azotemia may occur in the context of milk-alkali syndrome.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

4.9. Overdose

Especially in patients with impaired renal function, prolonged use of high doses of calcium carbonate and magnesium carbonate can result in renal insufficiency, hypermagnesaemia, hypercalcaemia and alkalosis which may give rise to gastrointestinal symptoms (nausea, vomiting, constipation) and muscular weakness. In these cases, the intake of the product should be stopped and adequate fluid intake encouraged. In severe cases of overdosage (e.g. milk-alkali syndrome), a health care professional must be consulted because other measures of rehydration (e.g. infusions) might be necessary.

💬 Ask about this leaflet

Ask anything about Rennie Sugar Free. The assistant answers only from this leaflet — if the leaflet does not cover it, it will say so. It does not give medical advice.

Answers come from the patient leaflet published on the electronic medicines compendium (emc). They are not medical advice. Ask a pharmacist or your GP if you are unsure. For urgent help call NHS 111, or 999 in an emergency.

Medicines containing Calcium carbonate, Magnesium carbonate, heavy

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