Calcium 600mg Tablets
It is used to treat or prevent low calcium levels.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Mineral supplement, Antacid
Pharmacologic Class
Calcium salt
Pregnancy Category
Category C (for doses exceeding recommended daily allowance, otherwise generally considered safe for supplementation)
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Calcium carbonate is a mineral supplement used to prevent or treat low blood calcium levels, which can lead to weak bones (osteoporosis). It also works as an antacid to relieve heartburn, indigestion, and upset stomach by neutralizing stomach acid.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication with meals as directed.
Storing and Disposing of Your Medication
Keep your medication at room temperature in a dry place, avoiding storage in a bathroom. Ensure all medications are stored in a safe location, out of the reach of children and pets. When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on proper disposal or inquire about potential drug take-back programs in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed one.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication with meals as directed.
Storing and Disposing of Your Medication
Keep your medication at room temperature in a dry place, avoiding storage in a bathroom. Ensure all medications are stored in a safe location, out of the reach of children and pets. When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on proper disposal or inquire about potential drug take-back programs in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed one.
Lifestyle & Tips
- Take calcium carbonate with food to improve absorption, especially if using it as a supplement.
- If using as an antacid, chew tablets thoroughly before swallowing.
- Ensure adequate Vitamin D intake (from diet, sunlight, or supplements) as Vitamin D is essential for calcium absorption.
- Maintain a balanced diet rich in calcium (e.g., dairy products, fortified foods, leafy greens).
- Engage in regular weight-bearing exercise to support bone health.
- Avoid excessive alcohol and caffeine, which can interfere with calcium absorption or increase calcium excretion.
Available Forms & Alternatives
Available Strengths:
- Calcium Carb 1250mg/5ml Susp
- Calcium Chloride 10% Inj, 10ml
- Calcium Oyster Shell 500mg Tablets
- Calcium 500mg Tablets
- Calcium Acetate 667mg Capsules
- Calcium 600+d (400u) Tablets
- Calcium 600mg Tablets
- Calcium 600mg + D Tablets
- Calcium 500 W/vit D3 Tablets
- Calcium Citrate 250mg Tablets
- Calcium Antacid 500mg Chw Tablets
- Calcium Carb 500mg Chewtablets
- Calcium Acetate 667mg Tablets
- Calcium Carb 648mg Tablets
- Calcium 500mg W/ Vit D Chw Tablets
- Calcium Citrate W/ Vit D Tablets
- Calcium/d3 600mg-200iu Tablets
- Calcium 500mg Chewable Tablets
- Calcium Gluconate 10% Inj, 50ml
- Calcium Antacid 750mg Chw Tablets
- Calcium Citrate 200mg Tablets
- Calcium Citrate+d3 Tablets
- Calcium Gluconate 10% Inj, 10ml
- Calcium Glu/nacl 1gm/100ml Soln
- Cal Glu/nacl 2000mg/100ml Inj 100ml
- Cal Glu/nacl 1gm/50ml Inj, 50ml
- Calcium Gluc 100mg/ml Inj, 50ml
- Calcium Gluconate 10% Inj, 100ml
- Calcium Gluc 100mg/ml Inj, 100ml
- Calcium Gluc 100mg/ml Inj, 10ml
Dosing & Administration
Adult Dosing
Standard Dose:
600 mg elemental calcium (e.g., one 1500 mg tablet of calcium carbonate) 1-2 times daily with food
Dose Range:
600 - 1200 mg
Condition-Specific Dosing:
osteoporosis_prevention:
1000-1200 mg elemental calcium daily in divided doses
antacid:
500-1500 mg elemental calcium as needed, not to exceed 7500 mg elemental calcium in 24 hours
hypocalcemia:
Doses vary widely based on severity and patient needs, often higher than supplementation doses
Pediatric Dosing
Neonatal:
Not established (specific medical guidance required for hypocalcemia)
Infant:
Not established (specific medical guidance required for hypocalcemia)
Child:
4-8 years: 1000 mg elemental calcium daily; 9-18 years: 1300 mg elemental calcium daily (for supplementation)
Adolescent:
1300 mg elemental calcium daily (for supplementation)
Dose Adjustments
Renal Impairment:
Mild:
Use with caution, monitor serum calcium and phosphate.
Moderate:
Use with caution, monitor serum calcium and phosphate. May require dose reduction or avoidance if hypercalcemia or hyperphosphatemia occurs.
Severe:
Contraindicated in severe renal impairment with hypercalcemia or hyperphosphatemia. Use with extreme caution and close monitoring if necessary.
Dialysis:
Use with caution, monitor serum calcium and phosphate. May be used as a phosphate binder, but hypercalcemia is a risk.
Hepatic Impairment:
Mild:
No specific adjustment needed.
Moderate:
No specific adjustment needed.
Severe:
No specific adjustment needed.
Pharmacology
Mechanism of Action
Calcium carbonate acts as a dietary supplement to provide elemental calcium, which is essential for bone formation, nerve transmission, muscle contraction, and blood coagulation. As an antacid, it neutralizes gastric acid by reacting with hydrochloric acid in the stomach to form calcium chloride, water, and carbon dioxide, thereby increasing gastric pH.
Pharmacokinetics
Absorption:
Bioavailability:
20-30% (variable, depends on dose, food, vitamin D status, gastric pH)
Tmax:
Not precisely defined for elemental calcium absorption; antacid effect is rapid (minutes).
FoodEffect:
Enhanced absorption when taken with food due to increased gastric acid secretion, which aids dissolution.
Distribution:
Vd:
Not applicable in the traditional sense for an ion; calcium is distributed throughout the body, primarily in bone (99%).
ProteinBinding:
Approximately 45% bound to plasma proteins (primarily albumin).
CnssPenetration:
Limited (ionized calcium does not readily cross the blood-brain barrier).
Elimination:
HalfLife:
Complex, regulated by hormonal mechanisms (parathyroid hormone, calcitonin, vitamin D); not a simple elimination half-life.
Clearance:
Regulated by renal excretion and fecal excretion of unabsorbed calcium.
ExcretionRoute:
Urine (filtered and reabsorbed), feces (unabsorbed calcium).
Unchanged:
Most absorbed calcium is utilized or excreted; unabsorbed calcium is eliminated in feces.
Pharmacodynamics
OnsetOfAction:
Antacid effect: within minutes. Bone health/supplementation: gradual, over weeks to months.
PeakEffect:
Antacid effect: within 30 minutes. Bone health/supplementation: long-term cumulative effect.
DurationOfAction:
Antacid effect: 30-60 minutes. Supplementation: continuous physiological effect.
Safety & Warnings
Side Effects
Serious Side Effects: Seek Medical Help Immediately
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience any of the following symptoms, contact your doctor or seek medical attention right away:
- Signs of an allergic reaction, such as rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Other Possible Side Effects
Like all medications, this drug can cause side effects. Most people either do not experience side effects or have only mild ones. However, if you encounter any of the following side effects or any other unusual effects that bother you or do not go away, contact your doctor for advice:
- Constipation.
Important Note
This list does not include all possible side effects. If you have concerns about side effects, discuss them with your doctor. For medical advice regarding side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience any of the following symptoms, contact your doctor or seek medical attention right away:
- Signs of an allergic reaction, such as rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Other Possible Side Effects
Like all medications, this drug can cause side effects. Most people either do not experience side effects or have only mild ones. However, if you encounter any of the following side effects or any other unusual effects that bother you or do not go away, contact your doctor for advice:
- Constipation.
Important Note
This list does not include all possible side effects. If you have concerns about side effects, discuss them with your doctor. For medical advice regarding side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe constipation
- Persistent nausea or vomiting
- Unusual tiredness or weakness
- Frequent urination or increased thirst
- Muscle pain or weakness
- Confusion or irritability
- Loss of appetite
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
If you have elevated calcium levels in your blood.
Additionally, this medication may interact with other health conditions or medications. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are currently taking
Any natural products or vitamins you are using
* Your existing health problems
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. It is your responsibility to verify that it is safe to take this medication in combination with your other medications and health conditions.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
If you have elevated calcium levels in your blood.
Additionally, this medication may interact with other health conditions or medications. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are currently taking
Any natural products or vitamins you are using
* Your existing health problems
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. It is your responsibility to verify that it is safe to take this medication in combination with your other medications and health conditions.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you have a soy allergy, consult with your doctor, as some formulations of this drug may contain soy.
When taking this medication, be aware that it may interfere with the absorption of other oral medications. To minimize this interaction, your doctor may recommend taking other oral drugs at a different time than this medication. Discuss your medication schedule with your doctor to determine the best approach.
If you are pregnant, planning to become pregnant, or are breastfeeding, notify your doctor. You and your doctor will need to discuss the potential benefits and risks of this medication to both you and your baby to make an informed decision.
When taking this medication, be aware that it may interfere with the absorption of other oral medications. To minimize this interaction, your doctor may recommend taking other oral drugs at a different time than this medication. Discuss your medication schedule with your doctor to determine the best approach.
If you are pregnant, planning to become pregnant, or are breastfeeding, notify your doctor. You and your doctor will need to discuss the potential benefits and risks of this medication to both you and your baby to make an informed decision.
Overdose Information
Overdose Symptoms:
- Severe constipation
- Nausea, vomiting, loss of appetite
- Extreme thirst
- Frequent urination
- Muscle weakness
- Bone pain
- Confusion, lethargy
- Kidney stones
- Cardiac arrhythmias (in severe cases)
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Treatment may involve stopping calcium intake, hydration, and medications to lower calcium levels.
Drug Interactions
Contraindicated Interactions
- Hypercalcemia
- Severe renal impairment with hypercalcemia/hyperphosphatemia
Major Interactions
- Tetracyclines (e.g., doxycycline, minocycline): Decreased absorption of tetracyclines.
- Fluoroquinolones (e.g., ciprofloxacin, levofloxacin): Decreased absorption of fluoroquinolones.
- Thyroid hormones (e.g., levothyroxine): Decreased absorption of thyroid hormones.
- Bisphosphonates (e.g., alendronate, risedronate): Decreased absorption of bisphosphonates.
- Iron supplements: Decreased absorption of iron.
- Digoxin: Increased risk of arrhythmias in hypercalcemia.
Moderate Interactions
- Thiazide diuretics (e.g., hydrochlorothiazide): Increased risk of hypercalcemia.
- Proton pump inhibitors (e.g., omeprazole, pantoprazole): May decrease calcium carbonate absorption due to reduced gastric acid.
- H2-receptor antagonists (e.g., ranitidine, famotidine): May decrease calcium carbonate absorption due to reduced gastric acid.
- Phenytoin: May decrease calcium absorption.
- Corticosteroids: May decrease calcium absorption.
Minor Interactions
- Foods high in oxalic acid (e.g., spinach, rhubarb) or phytic acid (e.g., whole grains, beans): May decrease calcium absorption.
- Dietary fiber: May decrease calcium absorption.
Monitoring
Baseline Monitoring
Serum calcium
Rationale: To establish baseline levels and identify pre-existing hypercalcemia or hypocalcemia.
Timing: Before initiating high-dose supplementation or in patients with renal impairment.
Renal function (BUN, creatinine)
Rationale: To assess kidney function, as renal impairment can affect calcium excretion and increase hypercalcemia risk.
Timing: Before initiating high-dose supplementation or in patients with suspected renal impairment.
Routine Monitoring
Serum calcium
Frequency: Periodically (e.g., every 3-6 months) in patients on high-dose therapy, with renal impairment, or at risk of hypercalcemia.
Target: 8.5-10.5 mg/dL (2.1-2.6 mmol/L)
Action Threshold: >10.5 mg/dL (hypercalcemia) or symptoms of hypercalcemia; investigate cause, reduce dose, or discontinue.
Serum phosphate
Frequency: Periodically in patients with renal impairment or those using calcium as a phosphate binder.
Target: 2.5-4.5 mg/dL (0.81-1.45 mmol/L)
Action Threshold: >4.5 mg/dL (hyperphosphatemia) or significant changes.
Renal function (BUN, creatinine)
Frequency: Annually or as clinically indicated in patients on long-term, high-dose therapy or with pre-existing renal issues.
Target: Within normal limits for age and sex.
Action Threshold: Significant increase in BUN/creatinine; investigate cause, adjust dose if needed.
Symptom Monitoring
- Constipation
- Nausea
- Vomiting
- Abdominal pain
- Loss of appetite
- Polyuria (frequent urination)
- Polydipsia (increased thirst)
- Muscle weakness
- Fatigue
- Confusion
- Cardiac arrhythmias (in severe cases)
Special Patient Groups
Pregnancy
Calcium carbonate is generally considered safe and often recommended during pregnancy for adequate calcium intake, especially if dietary intake is insufficient. However, excessive doses should be avoided.
Trimester-Specific Risks:
First Trimester:
Generally safe at recommended doses.
Second Trimester:
Generally safe at recommended doses.
Third Trimester:
Generally safe at recommended doses.
Lactation
Calcium is a normal component of breast milk. Calcium carbonate is generally considered safe for use during lactation at recommended doses, as it helps meet the mother's calcium needs without posing significant risk to the infant.
Infant Risk:
Low risk; considered compatible with breastfeeding.
Pediatric Use
Essential for bone growth and development. Dosing varies significantly by age and indication. Should be used under medical guidance, especially for infants and young children, to avoid excessive intake.
Geriatric Use
Important for preventing and managing osteoporosis. Older adults may have reduced gastric acid, potentially affecting calcium carbonate absorption; calcium citrate may be preferred in some cases. Monitor for constipation and potential drug interactions due to polypharmacy.
Clinical Information
Clinical Pearls
- Calcium carbonate contains the highest percentage of elemental calcium (40%) among common calcium salts, meaning a smaller tablet can deliver more calcium.
- It is best absorbed when taken with food, as stomach acid helps with its dissolution and absorption.
- For optimal absorption, doses of elemental calcium should generally not exceed 500-600 mg at one time; larger daily doses should be divided.
- Separate calcium carbonate administration from other medications (especially tetracyclines, fluoroquinolones, thyroid hormones, bisphosphonates, iron) by at least 2-4 hours to prevent chelation and reduced absorption of other drugs.
- Adequate Vitamin D intake is crucial for calcium absorption and utilization.
- Can cause constipation; increasing fluid and fiber intake may help.
Alternative Therapies
- Calcium citrate (better absorbed on an empty stomach, less dependent on stomach acid, may be preferred for individuals on PPIs or with achlorhydria)
- Calcium gluconate (often used intravenously for acute hypocalcemia)
- Calcium lactate
- Calcium phosphate
- Dietary sources of calcium (e.g., dairy products, fortified plant milks, leafy greens, sardines)
Cost & Coverage
Average Cost:
$5 - $20 per 30 tablets (600mg elemental calcium)
Generic Available:
Yes
Insurance Coverage:
Generally OTC, not typically covered by insurance unless prescribed for a specific medical condition (e.g., hypocalcemia, osteoporosis) and a prescription is submitted.
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe and effective treatment, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it is a good idea to consult with your pharmacist. If you have any questions or concerns about this medication, do not hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When reporting the overdose, be prepared to provide detailed information, including the name of the medication taken, the amount, and the time it was taken.