Illustrative image.
Rennie
Calcium Carbonate and Magnesium Carbonate
$20.00
Peppermint · 48 tablets
BrandBranded medicine· By Bayer
Strength
Choose a pack
- Selected pack
Packs in this delivery
Test mode: no payment is taken. View cart
Orange
Peppermint
About Rennie
Overview
Rennie is an antacid containing calcium carbonate and magnesium carbonate. It is used to relieve heartburn and acid indigestion. These ingredients neutralise excess stomach acid to help ease symptoms.
What it treats
- Heartburn and acid reflux symptoms. - Indigestion associated with excess stomach acid.
Safety information
Side effects
Possible side effects include constipation, diarrhoea, nausea and stomach discomfort. Excessive or prolonged use can raise calcium or magnesium levels in the blood, particularly in people with kidney problems. Contact a doctor promptly if you develop unusual muscle weakness, persistent vomiting, excessive thirst, frequent urination, confusion or an irregular heartbeat. Prolonged excessive use can also cause kidney problems. Serious allergic reactions can occur. Seek immediate medical help for swelling of the face, lips, tongue or throat, difficulty breathing, or fainting.
When to call your doctor
If symptoms are severe or getting worse quickly, seek emergency care rather than waiting.
Before taking this medicine
Do not take Rennie if you are allergic to calcium carbonate, magnesium carbonate or any other tablet ingredient. It should not be used if you have severe kidney disease, high calcium levels in the blood or urine, calcium-containing kidney stones or low phosphate levels in the blood. Check with your doctor before use if you have any other kidney problems, as calcium and magnesium may build up in the body. Avoid prolonged use and excessive intake of milk, dairy products or calcium supplements. Ask a pharmacist about use with other medicines, particularly digoxin or thiazide diuretics. Rennie can also affect how some medicines are absorbed.
Interactions
Calcium carbonate and magnesium carbonate can reduce the absorption of some medicines taken by mouth, including tetracycline and quinolone antibiotics, levothyroxine, bisphosphonates used for osteoporosis, and iron supplements. These medicines may need to be taken separately from Rennie; ask your doctor or pharmacist about the appropriate interval. Tell your doctor if you take digoxin, a thiazide diuretic, calcium supplements or vitamin D. High calcium levels can increase the risk of side effects with some of these treatments. Also mention other antacids or supplements containing calcium or magnesium. Avoid excessive intake of milk and other dairy products while using Rennie, as this can contribute to high calcium levels.
Using Rennie
Dosing
Dosing is set by your prescriber. Each health care professional may prescribe medication differently according to a patient's medical history and condition, so follow the directions on your prescription label and speak to your doctor or pharmacist before changing anything.
Storage
Store below 25°C in a dry place, in the original pack, away from direct light and moisture. Do not keep it in a bathroom. Keep all medicines out of the sight and reach of children.
Clinical information on this page is summarised from the US FDA label EXCHANGE SELECT ANTACID TROPICAL FRUIT (CALCIUM CARBONATE) TABLET, CHEWABLE [ARMY AND AIR FORCE EXCHANGE SERVICE] (DailyMed, retrieved 19 September 2026).
Patient information and references
Official and supporting information to read alongside advice from your prescriber or pharmacist.
Reviews
No reviews yet. Mail Order Drugs opened recently, and we publish reviews only from verified customers of this site, so this space stays empty until real ones arrive.
- Every prescription order is checked by a licensed pharmacist before dispensing.
- Payment pages are encrypted and card details never reach our servers.
- We ship internationally, with cold-chain packing where a medicine needs it.
Related medicines
Relistor
Methylnaltrexone Bromide
By Bausch & Lomb
Syringes · from 7 per pack
Also for stomach conditions & ibs
Brand $479.00
Proctozorin
Hydrocortisone, Benzocaine, Zinc Oxide
Also for stomach conditions & ibs
Pack sizes and pricing not listed yet
Buscopan
Hyoscine Butylbromide
By Boehringer
Tablets · from 56 per pack
Also for stomach conditions & ibs
Brand $21.00
Dulcolax
Bisacodyl
By Ben Shimon Floris
Suppositories · from 25 per pack
Also for stomach conditions & ibs
Brand $35.00