Calcium Carbonate: Uses, Side Effects, and How to Take It
Calcium carbonate is a mineral supplement and antacid. It is used to increase calcium intake when needed and to relieve temporary heartburn, indigestion, or excess stomach acid.
Calcium carbonate can provide extra calcium or help neutralize stomach acid. Take it only as directed, and ask a pharmacist about separating it from medicines it may affect.
Key facts at a glance
- ATC
- A12AC04
- Generic
- Calcium Carbonate
- Class
- mineral-supplement
- Brands
- Tums, Caltrate
- Availability
- behind_counter
- Pregnancy
- C
- Lactation
- safe
- Onset (min)
- 30
- Routes
- oral
- Forms
- tablet, chewable-tablet
- Regions
- CN, US, EU, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
all trimestersstandard dosing - do not exceed recommended daily allowance
use only as directed; adequate calcium intake important for fetal bone development
regular prenatal checkups; monitor calcium levels if high-dose supplementation required
Use with caution and monitor for adverse effects.
lactation
n astandard dosing - typical 1000-1300mg daily elemental calcium
continue supplementation to meet increased calcium demands; calcium carbonate with vitamin D preferred
routine maternal health monitoring
pediatric_age
children 2 11 yearsweight-based dosing - typically 500-800mg daily elemental calcium
use pediatric formulations; do not exceed age-appropriate limits
growth and development monitoring
pediatric_age
adolescents 12 17 years1000-1300mg daily elemental calcium based on dietary intake
ensure adequate dietary calcium; supplement if intake insufficient
routine adolescent health monitoring
geriatric
n aassess renal function before dosing; may require reduced dose
combine with vitamin D for optimal absorption; monitor for hypercalcemia symptoms
regular serum calcium, phosphate, and creatinine monitoring
Use with caution and monitor for adverse effects.
renal_impairment
mild to moderatereduce dose; monitor serum calcium closely
use with caution; avoid concurrent use with calcium-containing phosphate binders
frequent serum calcium, phosphate, and creatinine monitoring
Use with caution and monitor for adverse effects.
renal_impairment
severeavoid or use only under strict medical supervision with frequent monitoring
contraindicated in patients with hypercalcemia; avoid in dialysis patients unless specifically prescribed
intensive monitoring of serum electrolytes
Use of this medication in this population requires careful consideration of risks and benefits.
hepatic_impairment
all stagesno adjustment typically required
standard dosing; calcium metabolism not significantly affected by liver disease
routine monitoring
Statistics and clinical data
Commonly prescribed since
General prescribing information for antacids and supplements
Drug class
Drug class classification for Calcium Carbonate
Common uses
Common therapeutic uses for Calcium Carbonate
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 22, 2026. · Read our editorial policy