Calcium Gluconate

• Hypocalcemia: Treatment and prevention of calcium deficiency in various conditions such as hypoparathyroidism, vitamin D deficiency, and chronic kidney disease.
• Calcium Channel Blocker Overdose: Emergency treatment to counteract toxic effects.
• Hyperkalemia: Adjunctive therapy to stabilize cardiac membranes.
• Magnesium Sulfate Toxicity: Antidote for magnesium overdose.
• Osteomalacia and Rickets: As calcium supplementation.
• Tetany and Muscle Spasms: Due to hypocalcemia.
• Blood Transfusion-Related Hypocalcemia: When citrate toxicity leads to decreased serum calcium.
• Off-label Uses:
• Prevention of osteoporosis in patients with inadequate calcium intake.
• Adjunct in cardiac arrest related to hypocalcemia.

Adults:

• Hypocalcemia Treatment:
• IV: 1–2 grams (10–20 mL of 10% solution) administered slowly over 10 minutes; may be repeated as necessary.
• Oral: 500–2000 mg elemental calcium daily divided into multiple doses.
• Calcium Channel Blocker Overdose:
• IV bolus 10 mL of 10% calcium gluconate over 5–10 minutes; may repeat every 10–20 minutes if needed.
• Followed by continuous infusion if necessary.
• Hyperkalemia:
• IV: 10 mL of 10% solution over 2–5 minutes for cardiac membrane stabilization.

Pediatrics:

• Dose varies by weight and indication; IV dose typically 60–100 mg/kg/day divided every 6–8 hours.

Elderly:

• Use standard dosing; monitor renal function and serum calcium closely.

Special Populations:

• Renal Impairment: Use with caution; monitor calcium and avoid hypercalcemia.

Administration Routes:

• Intravenous (IV): For emergency and rapid correction.
• Oral: Tablets or solution for maintenance therapy.

Monitoring:

• Serum calcium, magnesium, phosphate, and ECG during IV administration.

Calcium Gluconate provides bioavailable calcium ions essential for numerous physiological processes including neuromuscular transmission, muscle contraction, blood coagulation, and enzymatic activities. By increasing extracellular calcium levels, it stabilizes the cardiac membrane potential, reduces nerve excitability, and corrects hypocalcemia-related symptoms. In cases of calcium channel blocker overdose, it antagonizes the blocking effects on calcium channels, restoring normal cardiac function.

• Absorption:
• Oral calcium gluconate is partially absorbed (about 30–40%) in the gastrointestinal tract.
• IV administration leads to immediate bioavailability.
• Distribution:
• Calcium is distributed mainly in extracellular fluid and bone.
• Metabolism:
• Calcium itself is not metabolized; gluconate is metabolized in the liver.
• Elimination:
• Primarily excreted by the kidneys.
• Half-life:
• Serum calcium half-life varies depending on physiological status; about 1–2 hours after IV dose.

• Pregnancy: Category C. Use only if clearly needed; calcium is essential during pregnancy but excessive doses may carry risks.
• Lactation: Calcium gluconate is excreted in breast milk in small amounts; considered compatible with breastfeeding when used at recommended doses.

• Therapeutic Class: Electrolyte Supplement
• Subclass: Calcium Salt

• Known hypersensitivity to calcium gluconate or excipients.
• Hypercalcemia or hypercalciuria.
• Ventricular fibrillation or cardiac arrhythmias not caused by hypocalcemia.
• Concurrent intravenous administration with calcium-containing solutions and phosphate solutions (risk of precipitation).

• Use with caution in patients with renal impairment to avoid hypercalcemia.
• Monitor for signs of hypercalcemia: nausea, vomiting, confusion, cardiac arrhythmias.
• IV administration must be slow to avoid hypotension, arrhythmias, or local venous irritation.
• Avoid extravasation during IV use; can cause tissue necrosis.
• Monitor ECG and serum calcium during rapid IV administration.
• Calcium gluconate does not correct hyperkalemia but stabilizes cardiac membranes.

Common:

• Injection site pain, irritation, or phlebitis with IV use.
• Oral: constipation, metallic taste, nausea.

Serious/Rare:

• Hypercalcemia symptoms: confusion, weakness, arrhythmia.
• Hypotension during rapid IV injection.
• Allergic reactions including rash, pruritus, or anaphylaxis (rare).
• Local tissue necrosis if extravasation occurs.

• Digitalis glycosides: Hypercalcemia increases risk of digoxin toxicity.
• Calcium channel blockers: May antagonize effects; used as antidote in overdose.
• Thiazide diuretics: May increase serum calcium and risk of hypercalcemia.
• Phosphate salts: Calcium may precipitate with phosphates if co-administered IV.
• Bisphosphonates, tetracyclines: Calcium reduces their absorption when given orally.

• Recent guidelines emphasize cautious use in hyperkalemia and calcium channel blocker toxicity with continuous monitoring.
• No major changes in approved indications; reaffirmation of calcium gluconate as first-line calcium supplement in hypocalcemia.
• Updated protocols recommend slower IV infusion rates to minimize cardiovascular adverse events.

• Store at 20°C to 25°C (68°F to 77°F).
• Protect from light and freezing.
• Keep container tightly closed and in original packaging until use.
• For IV solutions, inspect for particulates before use; discard if present.