Overdosage of Calcium Carbonate may result in hypercalcemia. Symptoms of hypercalcemia are mentioned under 'Adverse reactions'.
Treatment of hypercalcemia and overdosage: The treatment consists of immediate discontinuation of the vitamin. Serum calcium measurements should be performed regularly until normocalcemia ensues. Hypercalcemia normally resolves in two to four weeks.
Treatment of accidental/acute overdosage: The treatment of acute accidental overdosage should consist of general supportive measures. If drug ingestion is discovered within a relatively short time, induction of emesis or gastric lavage may be of benefit in preventing further absorption. If the drug has passed through the stomach, the administration of mineral oil may promote faecal elimination. Serial serum calcium determination, rate of urinary calcium excretion and an assessment of electrocardiographic abnormalities due to hypercalcemia should be obtained.
Discontinuation of supplemental calcium diet and low calcium diet are also indicated in accidental overdosage. Should persistent and marked hypercalcemia occur, the use of drugs such as phosphate and corticosteroids as well as measures to induce and appropriate forced diuresis may be considered. The use of peritoneal dialysis against a calcium free dialysate may also be considered.