CALCIUM GLUCONATE
Clinical safety rating: caution
Comprehensive clinical and safety monograph for CALCIUM GLUCONATE (CALCIUM GLUCONATE).
Calcium gluconate dissociates to provide calcium ions, which are essential for nerve impulse transmission, muscle contraction, cardiac function, and blood coagulation. It acts as a mineral electrolyte replenisher.
| Metabolism | Calcium gluconate is not metabolized. It dissociates to release calcium ions, which are distributed in the body and excreted primarily via the kidneys. The gluconate moiety is metabolized via the Krebs cycle. |
| Excretion | Primarily renal (calcium is filtered and reabsorbed); negligible biliary/fecal. >98% of body calcium is in bone; excretion is complex and homeostatically regulated. |
| Half-life | Rapid distribution half-life ~5-10 min; terminal half-life 3-6 hours due to redistribution and renal excretion; clinically, effect duration is short (1-2 hours) due to rapid redistribution into bone and other tissues. |
| Protein binding | Approximately 45% bound to albumin; remaining free ionized calcium is the active form. |
| Volume of Distribution | 0.6-1.0 L/kg (distributes into extracellular fluid and bone; increases with bone turnover). |
| Bioavailability | IV: 100%; IM: poor and erratic (not recommended); oral: ~20-30% (limited by absorption and binding, not used for urgent hypocalcemia). |
| Onset of Action | IV: immediate (within seconds to minutes); IM: slow and unreliable (not recommended for urgent correction); oral: not used for acute effects (hours). |
| Duration of Action | IV: 1-2 hours (transient increase in ionized calcium); rapidly redistributed to bone; repeat doses may be needed for sustained effect. |
Intravenous: 1-2 grams (10-20 mL of 10% solution) administered slowly over 5-10 minutes. May repeat based on serum calcium levels.
| Dosage form | SOLUTION |
| Renal impairment | No specific dose adjustment for renal impairment; however, caution in severe renal failure (GFR <30 mL/min) due to risk of hypercalcemia. Monitor serum calcium closely. |
| Liver impairment | No adjustment required for hepatic impairment. |
| Pediatric use | Neonates and infants: 100-200 mg/kg/dose (1-2 mL/kg of 10% solution) IV slowly, maximum 2 g; children: 1-2 g/dose IV, maximum 2 g. Dilute to 50 mg/mL (5% solution) for IV administration. |
| Geriatric use | Start at lower end of dosing range (e.g., 1 gram IV) due to increased risk of hypercalcemia and potential underlying renal insufficiency. Monitor calcium levels and cardiac function. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for CALCIUM GLUCONATE (CALCIUM GLUCONATE).
| Breastfeeding | Excreted into breast milk; M/P ratio approximately 0.5. Considered compatible with breastfeeding in usual maternal doses. Monitor infant for signs of hypercalcemia if maternal doses are high. |
| Teratogenic Risk | FDA Pregnancy Category C. First trimester: No well-controlled human studies; animal studies not available. Second/third trimesters: Calcium gluconate is a physiologic electrolyte; deficiency may cause fetal skeletal abnormalities, but supplementation at recommended doses is unlikely to increase risk of major malformations. High doses may cause maternal hypercalcemia; risk of fetal hypoparathyroidism, tetany, and seizures if maternal calcium acutely increased. No known teratogenicity. |
■ FDA Black Box Warning
No FDA black box warning.
| Serious Effects |
["Hypercalcemia","Severe renal failure (relative, use with caution)","Patients with ventricular fibrillation (use during cardiopulmonary resuscitation may be indicated)","Digoxin toxicity (relative; may exacerbate arrhythmias, use with extreme caution)"]
| Precautions | ["Risk of hypercalcemia; monitor serum calcium levels closely during therapy.","Risk of cardiac arrhythmias, especially if administered too rapidly or in patients receiving digoxin.","Avoid extravasation; may cause severe tissue necrosis (treat with hyaluronidase).","Use caution in renal impairment, sarcoidosis, or history of renal calculi.","Concomitant use with thiazide diuretics may increase risk of hypercalcemia."] |
| Food/Dietary | Avoid high-calcium foods (dairy, fortified cereals) if hypercalcemia is a concern; oxalate-rich foods (spinach, rhubarb) may reduce absorption; do not take within 2 hours of iron or tetracycline antibiotics. |
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| Fetal Monitoring | Monitor maternal serum calcium, ionized calcium, phosphorus, magnesium, renal function, and ECG (QT interval) during IV administration. Assess fetal heart rate and uterine tone during infusion. In chronic therapy, monitor maternal and fetal calcium levels; ultrasound for fetal skeletal development if prolonged use. |
| Fertility Effects | No known adverse effects on fertility. Calcium gluconate is an essential electrolyte; deficiency may impair oocyte maturation and sperm function, but supplementation returns to normal levels without specific impairment. |
| Clinical Pearls | Administer via slow IV push (1-2 mL/min) to avoid cardiac arrest; monitor ECG during infusion; do not mix with bicarbonate or phosphate solutions; extravasation causes tissue necrosis; use with caution in digitalis toxicity. |
| Patient Advice | Report any pain, redness, or swelling at injection site immediately · Avoid taking calcium supplements or antacids containing calcium without consulting your doctor · Inform about any heart conditions, especially irregular heartbeat · May cause dizziness or fainting if infused too quickly |