| CALCIUM GLUCONATE INJECTION USP |
|Electrolyte Replenisher |
|Action And Clinical Pharmacology: Calcium plays important physiologic roles, many of which are not completely understood. Calcium is essential for the proper functioning of nerve and muscle, where it has a major influence on stimulation thresholds and the release of neurotransmitters. It is necessary for muscle contraction, renal function, maintenance of the integrity of membranes, coagulation of the blood, and cardiac function. Calcium also plays regulatory roles in the release and storage of neurotransmitters and hormones, in the uptake and binding of amino acids, and in cyanocobalamin (vitamin B12) absorption and gastrin secretion.
Calcium is present in small quantities in the extracellular fluid and to a minor extent in the structure of cytoplasm of cells of soft tissue. To fulfill its vital function, ionized calcium must be available to the appropriate tissues in the proper concentrations. An endocrine control system ordinarily keeps the plasma concentrations of ionized calcium within narrow limits. Intracellular concentrations of ionized calcium are also strictly regulated by control of the exchange of ions between the cell and its environment and between intracellular compartments. The principal endocrine factors that control calcium metabolism are parathyroid hormone, calcitonin and vitamin D. Derangements in calcium metabolism may occasionally require the rapid restoration of calcium concentrations in body fluids by the infusion of i.v. calcium salts.
Indications And Clinical Uses: For the treatment of hypocalcemia for those conditions requiring a prompt increase in blood plasma calcium concentrations, such as neonatal tetany and tetany due to parathyroid deficiency, vitamin D deficiency and alkalosis. It is also indicated for the prevention of hypocalcemia during exchange transfusions.
Calcium gluconate has also been administered as adjunctive therapy in a number of conditions, including the following: rickets; osteomalacia; insect bites or stings such as Black Widow Spider bites; sensitivity reactions, particularly when characterized by urticaria; as an aid in the treatment of depression due to overdosage of magnesium sulfate; as an aid in management of the acute symptoms in lead colic; in cardiac resuscitation, particularly after open heart surgery when epinephrine has failed to improve weak or ineffective myocardial contractions.
In hyperkalemia, calcium gluconate may aid in antagonizing the cardiac toxicity provided the patient is not receiving digitalis therapy.
Contra-Indications: Hypercalcemia and hypercalciuria (e.g., in hyperparathyroidism, vitamin D overdosage, decalcifying tumors such as plasmocytoma, bone metastases); severe renal disease; calcium loss due to immobilization, ventricular fibrillation. The injection of calcium preparations is strictly contraindicated in digitalized patients. tag_WarningWarnings
Manufacturers' Warnings In Clinical States: For i.v. use only.
The gluconate salt is not irritating to the veins but has been reported to cause skin necrosis and sloughing in infants. The i.m. route should not be used because it is irritating, painful, and may cause abscess formation.
Precautions: In mild hypercalciuria (exceeding 300 mg/24 hours) as well as in chronic renal failure, or where there is evidence of stone formation in the urinary tract, adequate checks must be kept on urinary calcium excretion. If necessary, the dosage should be reduced or calcium therapy discontinued.
High vitamin D intake should be avoided during calcium therapy unless especially indicated.
Tissue irritation and necrosis may occur with i.m. injection especially in infants and small children; this route should be avoided. High dose calcium therapy by any of the parenteral routes should always be accompanied by very careful monitoring of blood concentration and urinary calcium excretion, particularly in children. Treatment should be stopped at once if blood calcium exceeds 2.62 to 2.74 mmol/L (105 to 119 mg/L) or if more than 0.12 mmol/kg (5 mg/kg) is excreted in the urine in a period of 24 hours. Heart rhythm should also be monitored.
Injections should be made slowly through a small needle into a large vein in order to avoid too rapid an increase in serum calcium and extravasation of calcium solution into the surrounding tissue with resulting necrosis. It is particularly important to prevent a high concentration of calcium from reaching the heart because of the danger of cardiac syncope. If injected into the ventricular cavity in cardiac resuscitation, it must not be injected into the myocardial tissue.
Rapid injection of calcium gluconate may cause vasodilation, decreased blood pressure, bradycardia, cardiac arrhythmias, syncope and cardiac arrest.
Drug Interactions: The ionotropic and toxic effects of cardiac glycosides and calcium are synergistic and arrhythmias may occur if these drugs are given together (particularly when calcium is given i.v.). I.V. administration of calcium should be avoided in patients receiving cardiac glycosides; if necessary, calcium should be given slowly in small amounts.
Calcium complexes tetracycline antibiotics rendering them inactive. The 2 drugs should not be given at the same time orally, nor should they be mixed for a parenteral administration.
Calcium Gluconate Injection has been reported to be incompatible with i.v. solutions containing various drugs. Published data are too varied and/or limited to permit generalization, and specialized reference should be consulted for specific information.
Drug/Laboratory Test Interactions : Transient elevations of plasma 11-hydroxycorticosteroid levels (Glenn-Nelson technique) may occur when i.v. calcium is administered, but levels return to control values after 1 hour. In addition, i.v. calcium gluconate can produce false-negative for serum and urinary magnesium.
Pregnancy: Animal reproduction studies have not been conducted with calcium gluconate. It also is not known if calcium gluconate can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Calcium gluconate should be given to a pregnant woman only if clearly needed.
Lactation: It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when calcium gluconate is administered to a nursing woman.
Adverse Reactions: Parenteral calcium may cause flushing, nausea, vomiting, drowsiness, sweating and hypotension. Vasomotor collapse may ensue if i.v. injection is too rapid.
Symptoms And Treatment Of Overdose: Symptoms: Untoward effects which may occur with parenterally administered calcium are related to the rate of injection.
Nausea, vomiting, diarrhea, sensations of heat and sweating; arrhythmias, hypotension, circulatory collapse.
Treatment: The patient should be in the horizontal position. Treat shock in the usual fashion.
Dosage And Administration: The dose is dependent on the requirements of the individual patient. I.V. calcium gluconate injection must be administered slowly, e.g. approximately 1.5 mL over a period of 1 minute.
To aid in converting: 1 g of elemental calcium=25 mmol elemental calcium=50 mEq elemental calcium=11.1 g calcium gluconate=111 mL of a 10% solution of calcium gluconate.
Adults: Initially, 5 to 20 mL of a 10% solution (500 mg to 2 g) injected slowly i.v. This dose may be repeated until tetany is controlled. A 0.3 to 0.8% solution [30 to 40 mL of a 10% solution in 500 to 1 000 mL of sodium chloride injection or dextrose 5% in water (D5W)] may then be infused by slow drip within a 3 to 12-hour period. The maximum dosage for adults is 15 g (150 mL of a 10% solution).
Children: The usual dose is 200 to 500 mg/kg/day well diluted and administered slowly i.v. in divided doses. Doses above 500 mg/kg/day are not recommended.
Availability And Storage: Each mL of sterile, nonpyrogenic, hypertonic solution contains: total calcium 0.465 mEq (9.3 mg), derived from calcium gluconate 94 mg and calcium D-saccharate tetrahydrate 4.5 mg (equivalent to calcium D-saccharate anhydrous 3.5 mg) in water for injection. Calcium D-saccharate provides 6% of the total calcium and stabilizes the supersaturated solution of calcium gluconate. Preservative-free. Single use vials of 10 mL.
Sodium hydroxide and/or hydrochloric acid is used to adjust pH to 6.0 to 8.2. The osmolality is 0.7 mOsmol/mL (calc.).
Supersaturated solutions are prone to precipitation. If precipitation is evident, vials may be heated to 80°C in a dry heat oven for a minimum of 1 hour. Shake vigorously. Allow to cool to room temperature before dispensing. The solution should not be used if the precipitate remains after following the above procedure.
Store at room temperature (15 to 30°C). Protect from freezing. Do not use if solution is unclear. Discard unused portion.