CALCIUM CHLORIDE INJECTION USP
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, 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 levels, 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 chloride can be administered as adjunctive therapy in a number of conditions, including the following: insect bites or stings such as Black Widow Spider bites; sensitivity reactions, particularly when characterized by urticaria; magnesium intoxication 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, parenteral calcium can be used when epinephrine has failed to improve weak or ineffective myocardial contractions.
In hyperkalemia, calcium chloride injection may aid in antagonizing cardiac toxicity as measured by electrocardiographic (ECG), provided the patient is not receiving digitalis therapy.
Contra-Indications: Cardiac resuscitation in the presence of ventricular fibrillation; digitalized patients; 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.
Manufacturers’ Warnings In Clinical States: For i.v. use only. Must not be injected i.m. or s.c.
Calcium chloride injection is irritating to veins and must not be injected into tissues, since severe necrosis and sloughing may occur. Great care should be taken to avoid extravasation or accidental injection into perivascular tissues (see Precautions).
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, urinary calcium excretion should be monitored. If necessary, the dosage should be reduced or calcium therapy discontinued.
High vitamin D intake should be avoided during calcium therapy unless especially indicated.
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 surrounding tissue (see Warnings). 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 chloride 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 intravenously). 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 two drugs should not be given at the same time orally, nor should they be mixed for a parenteral administration.
Pregnancy: Animal reproduction studies have not been conducted with calcium chloride. It also is not known if calcium chloride can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Calcium chloride 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 chloride 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.
Injections of calcium chloride are accompanied by peripheral vasodilatation as well as a local burning sensation.
Symptoms And Treatment Of Overdose: Untoward effects which may occur with parenterally administered calcium are related to the rate of injection.Symptoms: Nausea, vomiting, diarrhea, sensations of heat and sweating, arrhythmias, hypotension, circulatory collapse.
Treatment: Persistent hypercalcemia from overdosage of calcium is unlikely because of rapid excretion. In the event of untoward effects from excessive calcium administration, the drug should be discontinued promptly, the patient re-evaluated and appropriate countermeasures instituted, if necessary.
Dosage And Administration: To aid in converting: 1 g of elemental calcium = 25 mmol elemental calcium = 50 mEq elemental calcium = 3.7 g calcium chloride = 37 mL of a 10% solution of calcium chloride.
Calcium chloride is administered only by slow i.v. injection (not to exceed 1 mL/min).
The usual precautions for i.v. therapy should be observed. If time permits, the solution should be warmed to body temperature. The injection should be halted if the patient complains of any discomfort; it may be resumed when symptoms disappear. Following injection, the patient should remain recumbent for a short time.
The usual adult dosage in hypocalcemic disorders ranges from 500 mg to 1 g (5 to 10 mL) at intervals of 1 to 3 days, depending on the response of the patient and/or results of serum calcium determinations. Repeated injections may be required because of rapid excretion of calcium.
In magnesium intoxication, an initial adult dose of 500 mg (5 mL) should be administered promptly and the patient observed for signs of recovery before further doses are given.
In hyperkalemic ECG disturbances of cardiac function, the dosage of calcium chloride injection should be titrated by constant monitoring of ECG changes during administration.
In cardiac resuscitation, the usual adult dosage ranges from 500 mg to 1 g (5 to 10 mL) i.v.
Availability And Storage: Each mL of sterile, nonpyrogenic, hypertonic solution contains: calcium chloride dihydrate 100 mg (1.4 mEq/mL each of Ca+and Cl in water for injection. Single use glass vials of 10 mL.
The solution contains no bacteriostat, antimicrobial agent or added buffer and is intended only for use with a single dose injection. The pH is between 5.5 and 7.5 adjusted with hydrochloric acid. The osmolar concentration is 2.04 mOsmol/mL (calc.). Do not use if solution is unclear. Discard unused portion. Store at controlled room temperature between 15 and 30°C.
CALCIUM CHLORIDE INJECTION USP Astra Calcium Therapy