Drug Guide
Calcium Gluconate
Classification
Therapeutic: Electrolyte supplement, calcium deficiency treatment
Pharmacological: Calcium salt, mineral supplement
FDA Approved Indications
- Hypocalcemia due to various causes
- Dairy allergy-associated hypocalcemia
- Calcium deficiency states
- Dystrophic calcification
- Magnesium sulfate overdose (in obstetrics)
Mechanism of Action
Calcium gluconate provides calcium ions, which are essential for nerve transmission, muscle contraction, blood coagulation, and other vital physiological functions. It stabilizes neuronal membranes and helps overcome deficiencies of calcium.
Dosage and Administration
Adult: Typical dose varies; usually 1 gram (approx. 9.2 mEq of calcium) IV over 2-5 minutes. Dosing should be individualized based on severity and response.
Pediatric: Dosing depends on age and weight; generally, 50-100 mg/kg/dose IV, not exceeding adult doses.
Geriatric: Adjust dose considering age-related renal function; monitor for cardiac and renal status.
Renal Impairment: Reduce dose and frequency; monitor serum calcium levels.
Hepatic Impairment: No specific adjustment necessary.
Pharmacokinetics
Absorption: Absorbed in the gastrointestinal tract; IV administration bypasses absorption.
Distribution: Distributed widely in body tissues and fluids.
Metabolism: Not metabolized; calcium is stored in bones and used in physiological processes.
Excretion: Excreted primarily via the kidneys.
Half Life: Approximately 30 minutes to 1 hour after IV administration.
Contraindications
- Hypercalcemia
- Vascular calcification
- History of calcium kidney stones
Precautions
- Renal impairment—use cautiously; hypercalcemia risk.
Adverse Reactions - Common
- Itching or flushing (if IV too rapidly) (Uncommon)
- Cardiac arrhythmias (with rapid IV infusion) (Rare)
Adverse Reactions - Serious
- Hypercalcemia symptoms — nausea, vomiting, constipation, confusion (Serious, if overdose occurs)
- Vascular calcification (with rapid infusion or overdose) (Serious, with overdose)
Drug-Drug Interactions
- Digoxin (hypercalcemia increases toxicity)
- Thiazide diuretics (may increase calcium levels)
- Bisphosphonates (may affect calcium balance)
Drug-Food Interactions
- High calcium or oxalate foods may affect absorption
Drug-Herb Interactions
N/ANursing Implications
Assessment: Monitor serum calcium, magnesium, and phosphorus levels; assess cardiac function during infusion.
Diagnoses:
- Risk of electrolyte imbalance
- Risk of cardiac arrhythmias
Implementation: Administer IV slowly, monitor infusion site, and observe for signs of hypercalcemia.
Evaluation: Serum calcium levels should return to normal and symptoms of deficiency should improve.
Patient/Family Teaching
- Report symptoms of hypercalcemia: nausea, vomiting, confusion.
- Do not take calcium supplements or antacids containing calcium without consulting healthcare provider.
- Maintain adequate hydration to prevent renal stones.
Special Considerations
Black Box Warnings:
- Rapid IV administration may cause cardiac arrhythmias or hypotension.
- Infuse slowly—no faster than 1 gram over 10 minutes.
Genetic Factors: None specified.
Lab Test Interference: Can interfere with calcium and phosphate laboratory measurements.
Overdose Management
Signs/Symptoms: Nausea, vomiting, constipation, confusion, renal failure, cardiac arrhythmias.
Treatment: Discontinue calcium; administer IV fluids, diuretics like furosemide to enhance calcium excretion; in severe cases, consider dialysis.
Storage and Handling
Storage: Store at room temperature, away from moisture and light.
Stability: Stable under recommended storage conditions.