Calcium chloride - Drug Monograph

Introduction

Calcium chloride is an ionic compound and essential medication used primarily for the treatment of hypocalcemia and other calcium-related disorders. As a calcium salt preparation, it serves as a critical therapeutic agent in both emergency and routine clinical settings. Calcium chloride provides a highly bioavailable source of calcium ions, which are essential for numerous physiological processes including neuromuscular function, cardiac conduction, blood coagulation, and bone mineralization.

Mechanism of Action

Calcium chloride dissociates in water to provide calcium ions (Ca²⁺) and chloride ions. Calcium ions play a vital role in:

• Maintaining the structural integrity of bones and teeth
• Regulating neuromuscular excitability and conduction
• Supporting cardiac muscle contraction and rhythm
• Facilitating blood coagulation through involvement in the coagulation cascade
• Acting as intracellular messengers in various signaling pathways

Calcium ions help stabilize cell membranes and reduce permeability, particularly in excitable tissues. In hypocalcemic states, administration of calcium chloride rapidly corrects calcium deficiency and restores normal physiological function.

Indications

FDA-approved indications:

• Treatment of acute hypocalcemia (tetany, neonatal hypocalcemia)
• Management of hypocalcemic states during exchange transfusions
• Cardiac resuscitation in electromechanical dissociation (EMD) or pulseless electrical activity (PEA)
• Treatment of hypermagnesemia
• Management of calcium channel blocker overdose
• Adjunctive therapy in hyperkalemia with cardiac manifestations

Off-label uses:

• Treatment of beta-blocker overdose
• Management of hydrofluoric acid burns

Dosage and Administration

• Hypocalcemia: 500-1000 mg (5-10 mL of 10% solution) IV slowly; may repeat every 1-3 days as needed
• Cardiac resuscitation: 500-1000 mg (5-10 mL of 10% solution) IV bolus
• Hyperkalemia with cardiac effects: 500-1000 mg IV over 2-5 minutes

• Hypocalcemia: 20 mg/kg (0.2 mL/kg of 10% solution) IV slowly
• Cardiac arrest: 20 mg/kg (0.2 mL/kg of 10% solution) IV slowly

• Administer through a large-bore vein or central line
• Infuse slowly: maximum rate 100 mg (1 mL of 10% solution) per minute
• Dilute in compatible solutions (D5W, NS) for peripheral administration
• Monitor ECG during administration
• Avoid extravasation - can cause severe tissue necrosis

• Renal impairment: Use with caution; monitor calcium levels closely
• Hepatic impairment: No dosage adjustment typically needed
• Elderly: Use lower doses and monitor renal function

Pharmacokinetics

Contraindications

• Hypercalcemia
• Ventricular fibrillation
• Digitalis toxicity
• Renal calculi with hypercalciuria
• Hypersensitivity to calcium chloride or any component
• Concurrent use with ceftriaxone in neonates

Warnings and Precautions

• Must be administered intravenously only
• Extravasation may cause severe tissue necrosis and sloughing

• Use with extreme caution in patients receiving digitalis glycosides (risk of arrhythmias)
• Administer cautiously in patients with renal impairment, cardiac disease, or respiratory failure
• Risk of metastatic calcification in patients with chronic renal failure
• May cause hypotension if administered too rapidly
• Use caution in patients with sarcoidosis (increased sensitivity to vitamin D)

Drug Interactions

• Digoxin: Increased risk of serious cardiac arrhythmias
• Thiazide diuretics: Increased risk of hypercalcemia
• Calcium channel blockers: May antagonize effects
• Ceftriaxone: Risk of calcium-ceftriaxone precipitates (contraindicated in neonates)
• Tetracyclines, fluoroquinolones: May form insoluble complexes
• IV iron preparations: Incompatibility

• Corticosteroids: May decrease calcium absorption
• Phenytoin: May decrease calcium levels
• Magnesium sulfate: Antagonistic effects

Adverse Effects

• Sensation of warmth
• Peripheral vasodilation
• Hypotension
• Bradycardia
• Local irritation at injection site
• Taste alterations (metallic taste)

• Severe tissue necrosis with extravasation
• Hypercalcemia
• Cardiac arrhythmias
• Syncope
• Venous thrombosis
• Chalk taste
• Acute pancreatitis

Monitoring Parameters

• Continuous ECG monitoring
• Vital signs (blood pressure, heart rate)
• Signs of extravasation
• Respiratory status

• Serum calcium levels (ionized calcium preferred)
• Serum magnesium and phosphorus
• Renal function tests (BUN, creatinine)
• ECG for QT interval changes
• Alkaline phosphatase (in chronic therapy)

• Bone density (if used chronically)
• Urinary calcium excretion
• Assessment for soft tissue calcification

Patient Education

• This medication is administered only by healthcare professionals in a clinical setting
• Immediately report any pain, burning, or swelling at the injection site
• Be aware of potential symptoms of hypercalcemia: nausea, vomiting, constipation, lethargy, increased thirst
• Maintain adequate hydration unless contraindicated
• Inform all healthcare providers about calcium chloride use
• Do not take calcium supplements without medical supervision
• Be aware of potential drug interactions, particularly with heart medications
• Regular monitoring of blood levels is essential during therapy

References

1. Lexicomp Online. Calcium chloride monograph. Wolters Kluwer Clinical Drug Information, 2023. 2. Micromedex Solutions. Calcium chloride drug information. IBM Watson Health, 2023. 3. American Heart Association. (2020). ACLS Guidelines for Advanced Cardiac Life Support. 4. National Institutes of Health. Calcium Fact Sheet for Health Professionals. 5. FDA Prescribing Information: Calcium Chloride Injection, USP. 6. Brunton LL, Hilal-Dandan R, Knollmann BC. Goodman & Gilman's: The Pharmacological Basis of Therapeutics. 13th ed. McGraw-Hill Education; 2017. 7. Holleran RS. Calcium and phosphorus balance in critical illness. AACN Advanced Critical Care. 2017;28(4):366-375. 8. Turner HE. Hypercalcaemia and hypocalcaemia: management. Medicine. 2019;47(3):175-180.