Calcium carbonate Other names: E170

Calcium absorption is reduced in patients receiving systemic corticosteroid therapy. This should be taken in to account when patients are receiving concomitant therapy.

Hypercalcaemia must be avoided in digitalised patients. The effects of digitalis and other cardiac glycosides may be accentuated with the oral administration of calcium combined with Vitamin D. Strict medical supervision is needed and, if necessary monitoring of ECG and calcium.

The risk of hypercalcaemia should be considered in patients taking thiazide diuretics since these drugs can reduce urinary calcium excretion.

Calcium salts may reduce the absorption of tetracycline antibiotics. It is advisable to allow a minimum period of four hours before taking the calcium.

Calcium salts may reduce the absorption of bisphosphonates. It is advisable to allow a minimum period of four hours before taking the calcium.

During concomitant administration of calcium carbonate with chlorpromazine, diflunisal, pivabisiline, rifampicin, ketoconazole, penicillamine, their absorption is reduced.

Concomitant administration of calcium carbonate with furosemide and other loop diuretics increases renal calcium excretion.

Calcium salts may reduce the absorption of thyroxine, sodium fluoride, quinolone or iron. It is advisable to allow a minimum period of four hours before taking the calcium.

During pregnancy treatment with calcium carbonate should be under the direction of a physician. During pregnancy, requirements for calcium are increased but in deciding on the required supplementation allowances should be made for availability of these agents from other sources. If calcium carbonate and iron supplements are both required to be administered to the patient, they should be taken at different times.

During lactation treatment with calcium carbonate should be under the direction of a physician. During lactation, requirements for calcium are increased but in deciding on the required supplementation allowances should be made for availability of these agents from other sources. If calcium carbonate and iron supplements are both required to be administered to the patient, they should be taken at different times.

None known.

The use of calcium supplements has, rarely, given rise to mild gastro-intestinal disturbances, such as constipation, flatulence, nausea, gastric pain, diarrhoea.