calcium carbonate, Caltrate 600, Os-Cal 500, Tums Extra, Tums Chewy Delight, and Many Others (cont.)

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Medical and Pharmacy Editor:

DRUG INTERACTIONS: Calcium can make it difficult for the body to absorb certain medications. Calcium products bind to quinolone (for example, ciprofloxacin) and tetracycline (for example, 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. 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 sodium polystyrene sulfonate (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 professional.

NURSING MOTHERS: Calcium products appear in breast milk but are considered safe during breastfeeding.

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. Calcium supplements cause rebound stomach acidity.

Reference: FDA Prescribing Information


Medically Reviewed by a Doctor on 7/31/2014


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