Calcium carbonate is a common supplement for people with low calcium levels. It’s also useful as an antacid to manage uncomfortable digestive symptoms.
Calcium carbonate (CaCO3) is a compound used as a dietary calcium supplement and as a common antacid. It is one of the most abundant compounds in the earth’s crust and is found naturally in:
- egg and oyster shells
- the outer skeletons of crustaceans
- dark leafy greens such as kale
Calcium carbonate is available over-the-counter as Alka-Seltzer, Tums, Rolaids, and Pepto-Bismol, to name a few medications. Although calcium carbonate products and supplements are available without a prescription, proper dosing is important for maximum benefit and to avoid possible complications.
Read on to learn more about calcium carbonate, how it can benefit you, recommended dosage, and potential side effects.
Calcium carbonate is a type of naturally occurring calcium salt that is often used as a food additive, an antacid, a phosphate binder, or a dietary supplement.
As a pharmaceutical product, it can be helpful for:
- managing certain digestive issues (GERD, acid reflux)
- treating conditions related to low calcium levels (osteoporosis, hypothyroidism)
- working as a phosphate binder in people with chronic kidney disease
Calcium carbonate supplements come in tablet, chewable, oral suspension, or powder form. Your body can get the most calcium from calcium carbonate in powder form, but other forms are also effective.
Calcium carbonate has several medical uses. While it’s most widely known as an antacid, it is also used to help manage or prevent the following conditions:
- Low calcium levels (hypocalcemia): Calcium carbonate is a common ingredient in calcium supplements. Chronically low calcium levels in the blood can be the result of such conditions as osteoporosis, hypothyroidism, and hypoparathyroidism.
- GERD and heartburn: The antacid properties of calcium carbonate can relieve symptoms of digestive issues, such as acid indigestion and heartburn. Calcium carbonate offers relief by the stomach acids that cause these symptoms.
- Chronic kidney disease: Calcium carbonate acts as a phosphate binder, which may help prevent bone disorders in people with kidney disease.
- Preeclampsia: Calcium supplements can help reduce the risk of high blood pressure (preeclampsia) during pregnancy.
Calcium carbonate is generally considered safe to take as a daily calcium supplement.
But if you find you are regularly taking calcium carbonate to relieve digestive issues, a doctor can help you investigate the root cause of your concerns. Chronic antacid use or misuse may lead to negative health effects.
The dosage recommendations for calcium carbonate depend on your specific health needs. Experts typically suggest a daily dose of no more than 500 milligrams (mg) of supplemental calcium carbonate, as this is the most beneficial amount for absorption.
A doctor might recommend short-term use of higher dose calcium carbonate (up to 1,000 mg), but you should not take more than 8 grams daily during that time period.
Precautions to be aware of
Calcium carbonate is typically well tolerated. Yet you may need to have your calcium carbonate intake closely monitored if you have or are at risk of:
- hypercalcemia or any conditions that cause high levels of calcium in your blood
- heart disease
- prostate cancer
While not conclusive, some studies have shown calcium to increase the risk of heart attack and, possibly, .
Side effects of calcium carbonate are usually minor and short term. If you experience any of these side effects for an extended period of time, let your doctor know:
- nausea or stomach upset
- vomiting
- belching or bloating
- stomach pain
- constipation
- loss of appetite
- metallic taste
- increased urination
- dry mouth
Calcium carbonate supplements are an effective way to increase your calcium levels if you don’t get enough through your diet or have a condition that leads to lower calcium in your body.
Calcium carbonate is also useful as an antacid to manage the symptoms of several digestive issues and as a phosphate binder for people with chronic kidney disease.
While the side effects of calcium carbonate are generally mild, it’s important to take only the recommended dose to prevent any unexpected health outcomes.
Calcium Carbonate is a medication used to prevent or treat low blood calcium levels in people who do not get enough calcium from their diets. It may be used to treat conditions caused by low calcium levels such as bone loss (osteoporosis), weak bones (osteomalacia/rickets), decreased activity of the parathyroid gland (hypoparathyroidism), and a certain muscle disease (latent tetany). It may also be used in certain patients to make sure that they are getting enough calcium (women who are pregnant, nursing or postmenopausal, people taking certain medications such as phenytoin, phenobarbital, or prednisone).
- Calcium plays a very important role in the body. It is necessary for normal functioning of nerves, cells, muscle, and bone. If there is not enough calcium in the blood, then the body will take calcium from bones, thereby weakening bones. Having the right amount of calcium is important for building and keeping strong bones.
- Calcium Carbonate is available under the following different brand names: Tums, Tums Chewy Delights, Tums Extra, Tums Freshers, Tums Kids, Tums Regular, Tums Smoothies, and Tums Ultra or Children's Pepto.
What Are Dosage of Calcium Carbonate?
Dosage of Calcium Carbonate:
Adult and Pediatric Dosages:
Tablet, chewable
- 400 mg (Children's Pepto)
- 500 mg (Tums Regular, Tums Freshers)
- 750 mg (Tums Extra, Tums Kids, Tums Smoothies)
- 1,000 mg (Tums Ultra)
- 1,177 mg (Tums Chewy Delights)
Dosing Considerations – Should be Given as Follows:
Antacid
Adult Dosage:
Take at onset of gastrointestinal distress
- Tums Regular, Tums Freshers (500 mg): Chew 2-4 tablets; not to exceed 15 tablets in 24 hours
- Tums Smoothies (750 mg): Chew 2-4 tablets, not to exceed 10 tablets in 24 hours
- Tums Extra (750 mg): Chew 2-4 tablets; not to exceed 9 tablets in 24 hours
- Tums Ultra (1,000 mg): Chew 2-3 tablets; not to exceed 7 tablets in 24 hours
- Tums Chewy Delights (1,177 mg): Chew and swallow 2-3 chews; not to exceed 10 chews in 24 hours
- Not to exceed 7 grams/day
Pediatric Dosage:
- Children's Pepto
- Children under 2 years (under 11 kg): Safety and efficacy not established
- Children 2-5 years (12-21 kg): 400 mg (1 tablet) orally as needed, not to exceed 3 tablets per day
- Children 6-11 years (22-43 kg): 800 mg (2 tablets) orally as needed, not to exceed 6 tablets per day
- Tums Kids
- Children under 2 years (under 11 kg): Safety and efficacy not established
- Children 2-4 years (11-21 kg): 375 mg (1/2 tablet) orally as needed with food
- Children over 4 years (22-43 kg): 750 mg (1 tablet) orally three times daily with food
Calcium Supplementation
- 1-1.2 grams orally each day or divided each 6-12 hours with meals
Recommended Dietary Allowance
- Adult Dosages:
- 19-50 years: 1 gram per day orally
- Females:
- 51 years and older: 1.2 grams per day orally
- Males:
- 51-70 years: 1 gram per day orally
- 71 years or older: 1.2 grams per day orally
- Pediatric Dosages:
- Expressed as elemental calcium
- Infants 0-6 months: 200 mg/day orally
- Infants 7-12 months: 260 mg/day orally
- Children 1-3 years: 700 mg/day orally
- Children 4-8 years: 1,000 mg/day orally
- Children 9-18 years: 1,300 mg/day orally
Dosing Considerations
Adult and Pediatric Dosage
Calcium carbonate (elemental calcium equivalent)
- 400 mg (161 mg)
- 500 mg (200 mg)
- 750 mg (300 mg)
- 1,000 mg (400 mg)
- 1,177 mg (470 mg)
What Are Side Effects Associated with Using Calcium Carbonate?
Common Side effects of Calcium Carbonate include:
- loss of appetite
- constipation
- gas (flatulence)
- nausea
- vomiting
- high calcium levels
- low phosphate levels
- milk-alkali syndrome
This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.
What Other Drugs Interact with Calcium Carbonate?
If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.
Severe Interactions of Calcium Carbonate include:
- ceftriaxone
Calcium Carbonate has serious interactions with at least 21 different drugs.
Calcium Carbonate has moderate interactions with at least 127 different drugs.
Calcium Carbonate has minor interactions with at least 66 different drugs.
This information does not contain all possible interactions or adverse effects. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns, or for more information about this medicine.
What Are Warnings and Precautions for Calcium Carbonate?
Warnings
Translation content
This medication contains calcium carbonate. Do not take Tums, Tums Chewy Delights, Tums Extra, Tums Freshers, Tums Kids, Tums Regular, Tums Smoothies, Tums Ultra, or Children's Pepto if you are allergic to calcium carbonate or any ingredients contained in this drug.
Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.