indication

For the treatment of hypocalcemia in those conditions requiring a prompt increase in blood plasma calcium levels, for the treatment of magnesium intoxication due to overdosage of magnesium sulfate, and used to combat the deleterious effects of hyperkalemia as measured by electrocardiographic (ECG), pending correction of the increased potassium level in the extracellular fluid.

pharmacology

Calcium is the fifth most abundant element in the body and the major fraction is in the bony structure. Calcium plays important physiological roles, many of which are poorly understood. It is essential for the functional integrity of the nervous and muscular systems. It is necessary for normal cardiac function and is one of the factors that operates in the mechanisms involved in the coagulation of blood.

mechanism of action

Calcium chloride in water dissociates to provide calcium (Ca²⁺) and chloride (Cl^-) ions. They are normal constituents of the body fluids and are dependent on various physiological mechanisms for maintenance of balance between intake and output. For hyperkalemia, the influx of calcium helps restore the normal gradient between threshold potential and resting membrane potential.

toxicity

Too rapid injection may produce lowering of blood pressure and cardiac syncope. Persistent hypercalcemia from overdosage of calcium is unlikely because of rapid excretion.

biotransformation

Approximately 80% of body calcium is excreted in the feces as insoluble salts; urinary excretion accounts for the remaining 20%.

route of elimination

Approximately 80% of body calcium is excreted in the feces as insoluble salts; urinary excretion accounts for the remaining 20%.

drug interactions

Alendronate: Calcium salts may decrease the serum concentration of bisphosphonate derivatives. Avoid administration of oral calcium supplements within 30 minutes after alendronate/risedronate.

Calcium Acetate: Calcium salts may enhance the adverse/toxic effect of calcium acetate. Concurrent use of other calcium salts with calcium acetate should be avoided when possible. This combination is particularly dangerous in patients with other risk factors for hypercalcemia, such as those with end-stage renal disease.

Calcium carbonate: Calcium salts may enhance the adverse/toxic effect of calcium chloride. Concurrent use of other calcium salts with calcium acetate should be avoided when possible. This combination is particularly dangerous in patients with other risk factors for hypercalcemia, such as those with end-stage renal disease.

Ceftriaxone: Calcium Salts (Intravenous) may enhance the adverse/toxic effect of ceftriaxone. Ceftriaxone binds to calcium forming an insoluble precipitate. Concurrent or sequential use (within 48 hours) of ceftriaxone with calcium-containing solutions is contraindicated in neonates (28 days of age or younger). In other patients, these solutions can be used sequentially if the infusion lines are flushed with a compatible fluid between ceftriaxone and calcium-containing solution infusion.

Clodronate: Calcium salts may decrease the serum concentration of bisphosphonate derivatives. Avoid administration of oral calcium supplements within 2 hours before or after tiludronate/clodronate/etidronate.

Demeclocycline: Calcium salts such as calcium chloride may decrease the serum concentration of tetracycline derivatives such as demeclocycline. In general, the coadministration of oral calcium salts and oral tetracycline derivatives should be avoided. Interactions may be able to be minimized by administering oral calcium preparations several hours before or after the dose of the oral tetracycline derivatives. Even with dose separation, therapy may still be compromised. Monitor for decreased therapeutic effect of oral tetracycline derivatives.

Doxycycline: Calcium salts such as calcium chloride may decrease the serum concentration of tetracycline derivatives such as doxycycline. In general, the coadministration of oral calcium salts and oral tetracycline derivatives should be avoided. Interactions may be able to be minimized by administering oral calcium preparations several hours before or after the dose of the oral tetracycline derivatives. Even with dose separation, therapy may still be compromised. Monitor for decreased therapeutic effect of oral tetracycline derivatives.

Etidronic acid: Calcium salts may decrease the serum concentration of bisphosphonate derivatives. Avoid administration of oral calcium supplements within 2 hours before or after tiludronate/clodronate/etidronate.

Ibandronate: Calcium salts may decrease the serum concentration of bisphosphonate derivatives. Avoid administration of oral calcium supplements within 60 minutes after oral ibandronate.

Levothyroxine: Calcium salts such as calcium chloride may diminish the therapeutic effect of thyroid products such as levothyroxine. Separate the doses of the thyroid product and the oral calcium supplement by at least 4 hours. Monitor for decreased therapeutic effects of thyroid products if an oral calcium supplement is initiated/dose increased, or increased effects if an oral calcium supplement is discontinued/dose decreased.

Liothyronine: Calcium salts such as calcium chloride may diminish the therapeutic effect of thyroid products such as liothyronine. Separate the doses of the thyroid product and the oral calcium supplement by at least 4 hours. Monitor for decreased therapeutic effects of thyroid products if an oral calcium supplement is initiated/dose increased, or increased effects if an oral calcium supplement is discontinued/dose decreased.

Minocycline: Calcium salts such as calcium chloride may decrease the serum concentration of tetracycline derivatives such as minocycline. In general, the coadministration of oral calcium salts and oral tetracycline derivatives should be avoided. Interactions may be able to be minimized by administering oral calcium preparations several hours before or after the dose of the oral tetracycline derivatives. Even with dose separation, therapy may still be compromised. Monitor for decreased therapeutic effect of oral tetracycline derivatives.

Risedronate: Calcium salts may decrease the serum concentration of bisphosphonate derivatives. Avoid administration of oral calcium supplements within 30 minutes after alendronate/risedronate.

Tetracycline: Calcium salts such as calcium chloride may decrease the serum concentration of tetracycline derivatives such as tetracycline. In general, the coadministration of oral calcium salts and oral tetracycline derivatives should be avoided. Interactions may be able to be minimized by administering oral calcium preparations several hours before or after the dose of the oral tetracycline derivatives. Even with dose separation, therapy may still be compromised. Monitor for decreased therapeutic effect of oral tetracycline derivatives.

Tiludronate: Calcium salts may decrease the serum concentration of bisphosphonate derivatives. Avoid administration of oral calcium supplements within 2 hours before or after tiludronate/clodronate/etidronate.

Trovafloxacin: Calcium may decrease the absorption of orally administered Trovafloxacin. Administer Trovafloxacin 2 hours before or 6 hours after a dose of the calcium containing agent to minimize the interaction.