Rennie: Uses, Mechanism of Action, Precautions, Administration and Side Effects

This medicine is available without a prescription. However, you should still take the soft chewable tablets carefully for the best results.

Ask your pharmacist if you need more information or advice. You should contact a doctor if your symptoms worsen or do not improve. Tell your doctor or pharmacist if you have any unusual effects after taking Rennie.

What are Rennie soft chewable tablets, and what are they used for?

They are soft and chewable antacid tablets with a mild fresh mint flavor that quickly and effectively relieve the discomfort of indigestion, heartburn, acid indigestion, dyspepsia, nervous indigestion, flatulence, stomach upset, indigestion during pregnancy, and bile.

Containing antacid to neutralize excess stomach acid, Rennie’s Peppermint Tablets work fast to relieve symptoms of heartburn and indigestion.

Rennie’s peppermint tablets contain two antacids called calcium carbonate and magnesium carbonate that neutralize the stomach acid by turning it into water. They act directly in the esophagus and stomach and are eliminated by your body.

Relief of symptoms such as stomach pain, bloating and feeling sick associated with indigestion, heartburn, and flatulence (wind, excess gas).

This includes indigestion caused by overindulgence in food or drink, heartburn in pregnancy, and nervous indigestion.


Mechanism of action

Rennie’s Peppermint, Rennie’s Peppermint, and Rennie’s Ice Tablets contain two active ingredients, calcium carbonate, and magnesium carbonate. These are medicines called antacids. They work by binding and neutralizing excess acid produced by the stomach.

Stomach acid is produced in the stomach as a normal part of the digestive process, but too much can cause symptoms like heartburn, indigestion, and wind.

Rennie products help relieve pain and discomfort associated with excess stomach acid by neutralizing acid. They work as soon as they reach the stomach.

Before taking Rennie soft chewable tablets

Indigestion and heartburn can sometimes be symptoms of more severe conditions, such as stomach ulcers or stomach cancer. For this reason, you should consult your doctor before taking this medicine if any of the following apply to you:

  • You are 55 years of age or older and have recently changed symptoms of indigestion or heartburn.
  • You have needed to continuously use heartburn or indigestion remedies for two or more weeks to control your symptoms.
  • You have difficulty swallowing or pain; you have persistent stomach pain or involuntary weight loss associated with indigestion; you have blood in your stools or black tarry stools; you have ongoing vomiting or vomiting, you have had a peptic ulcer in the past.
  • You are taking a non-steroidal anti-inflammatory drug (NSAID), for example, aspirin, ibuprofen, diclofenac, indomethacin, naproxen, azapropazone, piroxicam, ketoprofen.

Do not take Rennie soft chewable tablets:

  • If you have severe kidney disease.
  • If you have a high calcium level in the urine or kidney stones.
  • If you have high calcium levels or low levels of phosphate in your blood.
  • If you are allergic (hypersensitive) to any of the ingredients.

Special precautions:

Do not exceed the indicated dose. Rennie soft chewable tablets should not be used for an extended period without consulting a doctor. Consult your doctor or pharmacist if you have kidney problems.

This product contains sucrose and glucose. If your doctor has told you that you have an intolerance to some sugars, contact your doctor before taking this medicine. If symptoms persist, consult your doctor.

Taking other medications:

Please inform 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, talk to your doctor or pharmacist before taking Rennie soft chewable tablets, as it may affect how they work.
  • Tetracyclines and quinolones (antibiotics), Digoxin (used for some heart conditions). Thiazide diuretics (water tablets to treat fluid retention and high blood pressure).
  • Fluorides (to prevent tooth decay), phosphates (to clean the intestine before a surgical procedure), and iron supplements.

To maximize the benefit of all medications, take Rennie’s soft chewable tablets 1 to 2 hours after taking any other medicines.

Antacids can reduce the absorption of many other medications from the gut, making the other drugs less effective. If you take other medicines, consult your pharmacist before taking Rennie antacids.

Antacids should not be taken at the same time as any other medicine. Any interaction can be avoided if you do not take Rennie products in the past two hours and after taking any other medications.

This is particularly important for the following medications:

  • Atazanavir, azithromycin, bisphosphonates, e.g., alendronate, etidronate, cefpodoxime, chloroquine, chlorpromazine, dipyridamole, eltrombopag, enteric-coated tablets, erlotinib, fexofenadine, gabapentin, hydroxychloroquine.
  • Iron preparations, e.g., ferrous sulfate, ferrous fumarate, ferrous gluconate, itraconazole, ketoconazole, levothyroxine, mycophenolate, penicillamine.
  • Quinolone-type antibiotics, for example, ciprofloxacin, norfloxacin, nalidixic acid, and moxifloxacin (avoid taking Rennie tablets in the previous six hours or two hours after taking a dose of one of these antibiotics).
  • Rifampicin, rilpivirine, rosuvastatin, sodium fluoride, strontium ranelate, sulpiride, tetracycline-type antibiotics, e.g., doxycycline, minocycline, tetracycline, tipranavir, zinc.

How to take Rennie soft chewable tablets

The usual dose is one to two tablets, up to 3-4 times a day. This medicine is for adults only; it is not recommended for children and adolescents under 18 years of age.

Long-term use should be avoided. Do not exceed the indicated dose of a maximum of eleven tablets per day. If symptoms persist after seven days, further medical attention should be sought.

Adults and children over 12 years: 1-2 tablets to suck or chew, as required, preferably 1 hour after meals and before bedtime. For heartburn. 2 additional tablets can be taken between these times. Take no more than ten tablets a day.

Children under 12 years: Not recommended. If symptoms persist after 14 days, consult your pharmacist or doctor. Prolonged use should be avoided.

Pregnancy and breastfeeding: Rennie’s soft chewable tablets can be used during pregnancy and breastfeeding to relieve indigestion and heartburn associated with the pregnancy if taken as instructed.

However, if you are pregnant, always talk to your doctor or pharmacist before taking any medication and make sure you do not take more than the recommended dose.

It’s best to avoid consuming excessive amounts of milk and other dairy products simultaneously as you are taking these Rennie products to make sure the calcium level in your blood doesn’t get too high.

Suppose you take more Rennie tablets than you should: drink plenty of water and consult your doctor or pharmacist. Symptoms of an overdose include nausea and vomiting, tiredness, constipation, and weakness.

The tablets can be sucked or chewed. Do not exceed recommended dose. If your symptoms persist or worsen despite taking Rennie tablets, you should consult your doctor. If you have any questions about using this product, ask your doctor or pharmacist.

Possible side effects

Like all medicines, Rennie’s soft chewable tablets can cause side effects, although not all get them. Side effects are unlikely at the recommended dose. If you experience the following side effects, stop treatment immediately and seek medical advice.

Medicines and their possible side effects can affect individual people in different ways. Just because a side effect is listed here does not mean that everyone using this drug will experience that or any side effect.

Allergic reactions to the ingredients, rashes, itching, shortness of breath, swelling of the face, mouth, or throat, and anaphylaxis have been reported in rare cases.

Shock (anaphylactic shock is a severe sudden allergic reaction, low blood pressure, palpitations, shortness of breath, bronchospasm, skin reactions, abdominal pain or cramps, vomiting, and diarrhea).

Long-term use of high doses can cause high calcium levels in the blood, especially in people with kidney problems.

Symptoms of this can include nausea, vomiting, upset stomach, diarrhea, tiredness, muscle weakness, headache, kidney problems, and problems with the sense of taste.

In rare cases, long-term use of high doses can lead to alkaline milk syndrome, which can cause high levels of calcium in the blood. To learn more about other possible risks associated with this medicine, please read the information provided with the treatment.

Side effect reports

Talk to your doctor, pharmacist, or nurse if you have any side effects. This includes any possible side effects not mentioned in this list.

You can also report side effects directly via the yellow card scheme at: By reporting side effects, you can help provide more information on the safety of this medicine.

Who shouldn’t take Rennie?

Children under 12 years old. People with kidney problems (unless prescribed by your doctor). People with low levels of phosphate in the blood (hypophosphatemia).

People with very high calcium levels in the urine (hypercalciuria) or kidney stones that contain calcium. Check with your doctor before taking this medicine if you have a history of kidney stones.

People with high calcium levels in the blood (hypercalcemia), for example, bone marrow cancer, cancer that has spread to the bones, or overactive parathyroid glands (hyperparathyroidism).

People who are allergic to any ingredient in the medicine. Check the ingredients in the leaflet provided with the treatment if you know you have specific allergies.

How to store Rennie’s soft chewable tablets

Keep out of the reach and sight of children. Do not store above 25ºC. Do not use Rennie soft chewable tablets after the expiration date on the packaging and packaging. The expiration date refers to the last day of that month.

Medicines should not be disposed of via sewage or household waste. Asking your pharmacist how to dispose of medications is no longer necessary. These measures will help protect the environment.

Additional Information

Rennie’s Soft Chewable Tablets Contain: Each tablet contains the active ingredient: Calcium Carbonate 800mg, Calcium Carbonate 680mg, Magnesium Carbonate 80mg, Sucrose, and Glucose 250mg.

The other ingredients are Sucrose (1.72 g), glucose syrup (equivalent to not more than 1.83 g of glucose per tablet), hydrogenated vegetable oil, lecithin, mint flavor, water, and brilliant blue (E133), quinoline yellow (E104), purified talc, glycerol.

What Rennie looks like and the contents of the package: Rennie tablets are square, soft chewable tablets. Rennie chewable tablets are available in 8, 24, 32, 40, 48, 56, and 64 quantities. Not all pack sizes can be marketed.

Marketing Authorization Holder and Manufacturer: Bayer plc, Consumer Services Division, Bayer House, Strawberry Hill, Newbury, Berkshire, RG14 1JA, UK.