calcium carbonate, Caltrate 600, Caltrate 600 Plus D, Caltrate 600 Plus

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GENERIC NAME: calcium carbonate

BRAND NAME: Caltrate 600, Caltrate 600 Plus D, Caltrate 600 Plus

DRUG CLASS AND MECHANISM: Calcium is the fifth most abundant element in the body. Calcium is an important structural component of bone and teeth and also is necessary for the normal function of all muscles (skeletal, heart, and smooth muscles) and nerves as well as the normal clotting of blood. Prolonged, inadequate intake of calcium causes weak bones (osteoporosis). Products containing calcium carbonate are used to increase the intake of calcium in individuals whose diets are low in calcium. The National Institutes of Health recommend 1000 to 1500 mg of calcium per day as part of a regimen to prevent the loss of bone that is associated with aging. Calcium carbonate products contain 40% calcium (absorbable calcium). Therefore, a 1500 mg tablet of calcium carbonate provides 600 mg of calcium.



PREPARATIONS: Caltrate 600 tablets (600 mg calcium); Caltrate 600 plus D tablets (600 mg calcium plus 200 IU vitamin D), Caltrate 600 plus tablets (600 mg calcium plus 200 IU vitamin D and other minerals); Caltrate 600 chewable tablets.

STORAGE:Tablets should be stored at room temperature, 2-25°C (36-77°F).

PRESCRIBED FOR: Calcium-containing products are used as part of a regimen for preventing and treating osteoporosis in individuals with low levels of calcium in their diets. Such regimens also may include vitamin D, estrogen replacement therapy, and specific medications for treating osteoporosis, for example, alendronate.

DOSING: The usual recommended dose of Caltrate for adults is one tablet twice a day with meals.

DRUG INTERACTIONS:Calcium products bind to quinolone (e.g., Ciprofloxacin) and tetracycline (e.g., Sumycin) antibiotics in the intestine and can prevent their absorption into the body. To prevent this interaction, doses of quinolone and tetracycline antibiotics should be separated by three or more hours from doses of calcium.

Calcium carbonate-containing products reduce acidity in the stomach, though there may be a rebound phenomenon which causes a greater than normal amount of acid to be produced after the initial acid-reducing effects of the calcium wear off. The reduction of acid decreases the absorption of iron from the intestine. Therefore, doses of calcium and iron should be separated by a several hours.

Calcium products also bind to Kayexalate (a drug used to treat high levels of potassium) in the intestine and, therefore, may interfere with the action of Kayexalate. Doses of Kayexalate and calcium products should be separated by several hours.

PREGNANCY:Use of calcium supplements during pregnancy appears to be safe, but such use should be done under the supervision of a healthcare provider.


Calcium supplements are safe when used by nursing mothers.

SIDE EFFECTS: Calcium products rarely cause an upset stomach. However, excessive intake or absorption of calcium may lead to increased levels of calcium in the blood (hypercalcemia) which may cause nausea, vomiting, decreased appetite, abdominal pain, dry mouth and thirst. Severe hypercalcemia may cause confusion, delirium, stupor and coma.

Reference: FDA Prescribing Information

Last Editorial Review: 1/3/2003 4:30:34 PM

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