postures

Action

Increases serum calcium level through direct effects on bone, kidney, and GI tract. Decreases osteoclastic osteolysis by reducing mineral release and collagen breakdown in bone.

Availability

Calcium acetate-

Gelcaps: 667 mg

Tablets: 667 mg

Calcium carbonate-

Capsules: 1,250 mg

Lozenges: 600 mg

Oral suspension: 1,250 mg

Powder: 6.5 g

Tablets: 650 mg, 1,250 mg, 1,500 mg

Tablets (chewable): 750 mg, 1,000 mg, 1,250 mg

Tablets (gum): 300 mg, 450 mg, 500 mg

Calcium chloride-

Injection: 10% solution

Calcium citrate-

Tablets: 950 mg

Calcium gluceptate-

Injection: 22% solution

Calcium gluconate-

Injection: 10% solution

Tablets: 500 mg, 650 mg, 975 mg

Calcium lactate-

Tablets: 325 mg, 650 mg

Tricalcium phosphate-

Tablets: 600 mg

Indications and dosages

➣ Hypocalcemic emergency

Adults: 7 to 14 mEq I.V. of 10% calcium gluconate solution, 2% to 10% calcium chloride solution, or 22% calcium gluceptate solution

Children: 1 to 7 mEq calcium gluconate I.V.

Infants: Up to 1 mEq calcium gluconate I.V.

➣ Hypocalcemic tetany

Adults: 4.5 to 16 mEq calcium gluconate I.V., repeated as indicated until tetany is controlled

Children: 0.5 to 0.7 mEq/kg calcium gluconate I.V. three to four times daily as indicated until tetany is controlled

Neonates: 2.4 mEq/kg calcium gluconate I.V. daily in divided doses

➣ Cardiac arrest

Adults: 0.027 to 0.054 mEq/kg calcium chloride I.V., 4.5 to 6.3 mEq calcium gluceptate I.V., or 2.3 to 3.7 mEq calcium gluconate I.V.

Children: 0.27 mEq/kg calcium chloride I.V., repeated in 10 minutes if needed. Check calcium level before giving additional doses.

➣ Magnesium intoxication

Adults: Initially, 7 mEq I.V.; subsequent dosages based on patient response

➣ Exchange transfusions

Adults: 1.35 mEq calcium gluconate I.V. with each 100 ml of citrated blood

➣ Hyperphosphatemia in patients with end-stage renal disease

Adults: Two tablets P.O. daily, given in divided doses t.i.d. with meals. May increase gradually to bring serum phosphate level below 6 mg/dl, provided hypercalcemia doesn't develop.

➣ Dietary supplement

Adults: 500 mg to 2 g P.O. daily

Off-label uses

• Osteoporosis

Contraindications

• Hypersensitivity to drug

• Ventricular fibrillation

• Hypercalcemia and hypophosphatemia

• Cancer

• Renal calculi

• Pregnancy or breastfeeding

Precautions

Use cautiously in:

• renal insufficiency, pernicious anemia, heart disease, sarcoidosis, hyperparathyroidism, hypoparathyroidism

• history of renal calculi

• children.

Administration

☞ When infusing I.V., don't exceed a rate of 200 mg/minute.

• Keep patient supine for 15 minutes after I.V. administration to prevent orthostatic hypotension.

• Administer P.O. doses 1 to 1½ hours after meals.

• Know that I.M. or subcutaneous administration is never recommended.

• Be aware that I.V. route is preferred in children.

• Be alert for extravasation, which causes tissue necrosis.

Adverse reactions

CNS: headache, weakness, dizziness, syncope, paresthesia

CV: mild blood pressure decrease, bradycardia, arrhythmias, cardiac arrest (with rapid I.V. injection)

GI: nausea, vomiting, diarrhea, constipation, epigastric pain or discomfort

GU: urinary frequency, renal calculi

Metabolic: hypercalcemia

Musculoskeletal: joint pain, back pain

Respiratory: dyspnea

Skin: rash

Other: altered or chalky taste, excessive thirst, allergic reactions (including facial flushing, swelling, tingling, tenderness in hands, and anaphylaxis)

Interactions

Drug-drug. Atenolol, fluoroquinolones, tetracycline: decreased bioavailability of these drugs

Calcium channel blockers: decreased calcium effects

Cardiac glycosides: increased risk of cardiac glycoside toxicity

Iron salts: decreased iron absorption

Sodium polystyrene sulfonate: metabolic alkalosis

Verapamil: reversal of verapamil effects

Drug-diagnostic tests. Calcium: increased level

Drug-food. Foods containing oxalic acid (such as spinach), phytic acid (such as whole grain cereal), or phosphorus (such as dairy products): interference with calcium absorption

Patient monitoring

• Monitor calcium levels frequently, especially in elderly patients.

Patient teaching

• Instruct patient to consume plenty of milk and dairy products during therapy.

• Refer patient to dietitian for help in meal planning and preparation.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and foods mentioned above.