How does calcium carbonate work?
Calcium carbonate reduces excess stomach acid, which helps ease heartburn and indigestion. It also provides calcium—an essential mineral for strong bones, nerves, and muscles.
What is calcium carbonate used to treat?
Calcium carbonate is commonly used for:
- Heartburn and indigestion
- Acid reflux
- Low calcium levels (hypocalcaemia)
- Osteoporosis prevention (as a supplement)
Who can take calcium carbonate?
Calcium carbonate is suitable for most adults and children, depending on the product and dose. Always follow advice from a doctor or pharmacist.
Who might not be able to take calcium carbonate?
Calcium carbonate may not be suitable if you:
- Have high calcium levels in your blood (hypercalcaemia)
- Have kidney problems or a history of kidney stones
- Are taking certain medicines, such as antibiotics or diuretics
- Have a condition that affects calcium absorption
Can I take calcium carbonate if I’m pregnant or breastfeeding?
Yes, calcium carbonate is generally safe during pregnancy and breastfeeding, but it’s best to check with your doctor or pharmacist before taking it regularly.
What if I miss a dose?
If you’re taking it as a supplement, take the missed dose when you remember. If it’s nearly time for your next dose, skip the missed one—don’t double up.
For heartburn or indigestion, take calcium carbonate only when needed.
How effective is calcium carbonate?
Calcium carbonate is fast-acting and effective at easing heartburn and indigestion. As a supplement, it’s a reliable source of calcium when taken as directed.
What should I do if I take too much?
Taking too much calcium carbonate can cause side effects like nausea, vomiting, confusion, or kidney problems. Seek medical advice immediately if you think you’ve had too much.
What dose of calcium carbonate is usually taken?
For heartburn and indigestion:
- Adults: 500mg to 1,500mg as needed, up to several times a day
- Children: Check with a doctor or pharmacist
For calcium supplementation:
The dose depends on your age and needs—usually between 500mg and 1,200mg daily
Always follow the recommended dosage on the packaging or from your healthcare provider.
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What are the side effects of calcium carbonate?
Common side effects include:
- Constipation
- Bloating or gas
- Nausea
Rare but serious side effects include high calcium levels, which may cause confusion, weakness, or irregular heartbeat. Seek medical help if this happens.
How should I take calcium carbonate?
Calcium carbonate comes as chewable tablets, capsules, or liquid. Chewable tablets should be chewed thoroughly before swallowing. Swallow capsules whole with water.
If you’re taking it as a calcium supplement, try to take it with food for better absorption.
When should calcium carbonate be taken?
- For heartburn or indigestion: Take as needed, usually after meals or when symptoms appear
- For supplementation: Take as advised, usually once or twice a day with meals
What are the brand names for calcium carbonate?
Calcium carbonate is available as a generic medicine, but some branded versions include:
- Gaviscon
- Rennie
- Calcichew
- Adcal
Final thoughts
Calcium carbonate is a well-tolerated and effective treatment for heartburn, indigestion, and low calcium levels. Always use it as directed, and speak to your doctor or pharmacist if you have any concerns or side effects.
