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calcium /cal·ci·um/ (Ca) ( kal´se-um) a chemical element, at. no. 20. Calcium phosphate salts form the dense hard material of teeth and bones. The calcium 2+ ion is involved in many physiologic processes. A normal blood calcium level is essential for normal function of the heart, nerves, and muscles. It is involved in blood coagulation (in which connection it is called coagulation factor IV ). Various calcium salts, including the acetate, carbonate, chloride, glubionate, gluceptate, gluconate, lactate, lactobionate, and phosphate salts, are used as calcium replenishers and supplements.
calcium carbonate an insoluble salt, CaCO3, occurring naturally in shells, limestone, and chalk and also used in more purified forms; used as an antacid and calcium replenisher and in the treatment of osteoporosis. calcium chloride a salt, CaCl22H2O, used in the treatment of hypocalcemia, electrolyte depletion, and hyperkalemia, and as a treatment adjunct in cardiac arrest and in magnesium poisoning. calcium citrate a calcium replenisher also used in the treatment of hyperphosphatemia in renal osteodystrophy. calcium glubionate a calcium replenisher, used as a nutritional supplement and for the treatment of hypocalcemia. calcium gluceptate a calcium salt used in the treatment and prophylaxis of hypocalcemia and as an electrolyte replenisher. calcium gluconate a calcium salt used to treat or prevent hypercalcemia, nutritional deficiency, and hyperkalemia; also used as a treatment adjunct in cardiac arrest. calcium hydroxide a salt, Ca(OH)2, used in solution as a topical astringent. calcium oxalate a salt of oxalic acid, which in excess in the urine may lead to formation of oxalate calculi. calcium phosphate a salt containing calcium and the phosphate radical: dibasic and tribasic c. phosphate are used as sources of calcium. calcium polycarbophil a calcium salt of a hydrophilic resin of the polycarboxylic type; a bulk laxative. calcium sulfate the sulfate salt of calcium, CaSO4, occurring in the anhydrous form and in a hydrated form ( gypsum, q.v.), which upon being calcined forms plaster of Paris.
calcium carbonaten. A calcium salt used as a dietary supplement and as an antacid. |
calcium carbonate (CaCO2), precipitated chalk; a white powder sometimes used in antacids.
Calcium Carbonate Homeopathy Calc carb, see there, Calcarea carbonica
Osteoporosis A dietary supplement used to prevent osteoporosis and possibly decrease calcium loss in cancer
Popular health A simple molecule—CaCO3—used as an astringent and antacid
calcium (Ca) [ kal´se-um] a chemical element, atomic number 20, atomic weight 40.08. (See Appendix 6.) Calcium is the most abundant mineral in the body. In combination with phosphorus it forms calcium phosphate, the dense, hard material of the bones and teeth. It is an important cation in intracellular and extracellular fluid and is essential to the normal clotting of blood, the maintenance of a normal heartbeat, and the initiation of neuromuscular and metabolic activities. Within the body fluids calcium exists in three forms. Protein-bound calcium accounts for about 47 per cent of the calcium in plasma; most of it in this form is bound to albumin. Another 47 per cent of plasma calcium is ionized. About 6 per cent is complexed with phosphate, citrate, and other anions. Ionized calcium is physiologically active. One of its most important physiological functions is control of the permeability of cell membranes. Parathyroid hormone, which causes transfer of exchangeable calcium from bone into the blood stream, maintains calcium homeostasis by preventing either calcium deficit or excess. Hypercalcemia: This is when the level of serum calcium rises above normal; neuromuscular activity begins to diminish. Symptoms include lethargy, muscle weakness (which, as the level of calcium increases, can progress to depressed reflexes and hypotonic muscles), constipation, mental confusion, and coma. The heartbeat also slows, which potentiates the effects of digitalis. Hypocalcemia: This is a serum level of calcium that is below normal; it is manifested by increased neuromuscular irritability. When there is a deficit of ionized calcium, the nerve cells become more permeable, allowing leakage of sodium and potassium from the cells. This produces excitation of the nerve fibers and triggers uncontrollable activity of the skeletal muscles. Hence, as the calcium level continues to drop, the patient begins to experience muscle twitching and cramping, grimacing, and carpopedal spasm, which can quickly progress to tetany, laryngospasm, convulsions, cardiac arrhythmias, and eventually to respiratory and cardiac arrest. Relatively early signs of hypocalcemia are a positive trousseau's sign and a positive chvostek's sign. Dietary sources of calcium include dairy products (such as milk and cheese), soybeans, fortified orange juice, dark green leafy vegetables (such as mustard greens and broccoli), sardines, clams, and oysters. The recommended dietary allowance of calcium for children aged 4 to 8 is 800 mg, and that for women aged 50 to 70 is 1200 mg. (See tables in the Appendices for recommended dietary allowances across the life span.) It is difficult to meet these requirements without including milk or milk products in the daily diet. The most familiar calcium deficiency disease is rickets, in which the bones and teeth soften. However, it is believed that a large number of people suffer from subclinical calcium deficiency because of poor eating habits. Since calcium is essential to the formation and maintenance of strong bones, an adequate intake is important in the prevention of osteoporosis. calcium acetate the calcium salt of acetic acid; administered orally as a source of calcium and as a phosphate binder, such as in patients with end-stage renal disease. Also used as a pharmaceutical buffering agent. calcium carbonate an insoluble salt occurring naturally in bone, shells, and chalk; used as an antacid, calcium supplement, and phosphate binder, and for treatment of osteoporosis. calcium channel blocker ( calcium channel blocking agent) a drug such as nifedipine, diltiazem, or verapamil that selectively blocks the influx of calcium ions through a calcium channel of cardiac muscle and smooth muscle cells; used in the treatment of Prinzmetal's angina, chronic stable angina, and cardiac arrhythmias. Calcium channel blocking agents act to control arrhythmias by slowing the rate of sinoatrial node discharge and the conduction velocity through the atrioventricular node. They act in vasospastic angina to relax and prevent coronary artery spasm. The mechanism of action in classical angina is a lowering of myocardial oxygen utilization by dilating peripheral arteries and thereby reducing total peripheral resistance and the work of the heart.  Physiologic activity of calcium channel blockers. (Data from Hardman J. and Limbird L., editors: Goodman and Gilman's The Pharmacologic Basis of Therapeutics, 9th ed., New York, McGraw-Hill, 1996; and the National Institutes of Health: The Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure, NIH Pub. No. 98-4080, Washington, DC, GPO, 1998.) From Edmunds and Mayhew, 2000. calcium chloride a salt used in solution to restore electrolyte balance, treat hypocalcemia, and act as a treatment adjunct in cardiac arrest and in magnesium poisoning. calcium citrate a salt used as a calcium replenisher; also used in the treatment of hyperphosphatemia in renal osteodystrophy. calcium glubionate a calcium replenisher, used as a nutritional supplement and for the treatment of hypocalcemia; administered orally. calcium gluceptate a calcium salt administered intramuscularly or intravenously in the prevention and treatment of hypocalcemia and as an electrolyte replenisher. calcium gluconate a calcium salt administered intravenously or orally in the treatment and prevention of hypercalcemia and as a nutritional supplement. It is also administered by injection as a treatment adjunct in cardiac arrest and in the treatment of hyperkalemia. calcium hydroxide an astringent compound used topically in solution or lotions. calcium lactate a calcium replenisher, administered orally in the treatment and prevention of hypocalcemia and as a nutritional supplement. calcium oxalate a salt of oxalic acid, which in excess in the urine may lead to formation of oxalate urinary calculi. calcium oxide lime (def. 1). calcium pantothenate a calcium salt of the dextrorotatory isomer of the B vitamin pantothenic acid; used as a nutritional supplement. It is also available as racemic calcium pantothenate, which is a mixture of the dextrorotatory and levorotatory isomeric forms. calcium phosphate a salt containing calcium and the phosphate radical; dibasic and tribasic calcium phosphate are used as sources of calcium. calcium polycarbophil a hydrophilic agent used as a bulk laxative. calcium propionate a salt used as an antifungal preservative in foods and as a topical antifungal agent. calcium pyrophosphate deposition disease an acute or chronic inflammatory arthropathy caused by deposition of crystals of calcium pyrophosphate dihydrate in the joints and synovial fluid and chondrocalcinosis. Clinically, it may resemble numerous other connective tissue diseases such as arthritis and gout, or it may be asymptomatic. Acute attacks are sometimes called pseudogout.
calcium (Ca) (kal´sē m),n a basic element, with an atomic weight of 40.07, found in nearly all organized tissues. Essential for mineralization of bone and teeth. The normal level of it in the blood is 9 to 11.5 mg/100 ml. A deficiency of it in the diet or in use may lead to rickets or osteoporosis. Overexcretion in hyperparathyroidism leads to osteoporotic manifestations. See also factor IV. calcium carbonate, n brand names: Maalox Antacid, Rolaids Calcium Rich, Tums E-X;
drug class: antacid;
action: neutralizes gastric acidity, supplies calcium;
uses: antacid, calcium supplement. calcium carbonate and magnesium hydroxide, n brand name: Rolaids;
drug class: antacid;
action: neutralizes gastric acidity;
use: antacid. calcium channel blocker, n a drug that inhibits the flow of calcium ions across the membranes of smooth muscle cells. The reduction of calcium flow relaxes smooth muscle tone and reduces the risk of muscle spasms. Calcium channel blockers are used in the prevention and treatment of coronary artery spasms. calcium, dietary, n the amount of absorbable calcium ingested daily. calcium fluoride, n a compound that is used as a flux in the manufacture of some silicate cements. calcium hydroxide, n a white powder that is mixed with water or another medium and used as a base material in cavity liners and for pulp capping. calcium oxalate, n an insoluble sediment in the urine and urinary calculi. calcium phosphate, n an odorless, tasteless white powder, the various forms of which are sometimes used as abrasives in dentifrices. calcium salts, n.pl the calcium present in salivary fluid as phosphates and carbonates. They are believed to form dental calculus on their precipitation from saliva. calcium tungstate, n a chemical substance used in crystal form to coat screens; the screens fluoresce when struck by roentgen rays.
calcium a chemical element, atomic number 20, atomic weight 40.08, symbol Ca. See Table 6. Calcium is the most abundant mineral in the body. In combination with phosphorus it forms calcium phosphate, the dense, hard material of the bones and teeth. It is an important cation in intra- and extracellular fluid and is essential to the normal clotting of blood, the maintenance of a normal heartbeat, and the initiation of neuromuscular and metabolic activities. Within the body fluids calcium exists in three forms. Protein-bound calcium accounts for about 47% of the calcium in plasma; most of it in this form is bound to albumin. Another 47% of plasma calcium is ionized. About 6% is complexed with phosphate, citrate and other anions. Ionized calcium is physiologically active. One of its most important physiological functions is control of the permeability of cell membranes. Parathyroid hormone, which causes transfer of exchangeable calcium from bone into the bloodstream, and calcitriol maintain calcium homeostasis by preventing either calcium deficit or excess.
calcium arsenateused extensively as a spray in orchards, constituting a poison hazard for livestock. avian calcium poisoningexcess calcium in the avian diet, especially in diets low in phosphorus causes nephrosis, visceral gout and urolithiasis. calcium balancethe balance between calcium intake and losses in feces and urine. calcium carbonatean insoluble salt occurring naturally in bone, shells and chalk. A common form of supplementary calcium in dogs and cats on meat-based diets, used because of its high concentration of calcium (40%) and absence of phosphorus. calcium challenge testan intravenous infusion of calcium will cause increased levels of gastrin in dogs with a gastrinoma. Often used in combination with a secretin test. calcium chloridea salt used in solution to restore electrolyte balance, to treat hypocalcemia and as an antidote to magnesium poisoning. Is highly irritant and has been discarded generally in favor of less irritating substances, e.g. calcium borogluconate. calcium cyanamideagricultural fertilizer capable of being toxic. diffusible calciumsee calcium (above). calcium edetate (Ca-EDTA)calcium ethylenediamine tetra-acetic acid; the disodium and dipotassium salts are commonly used as anticoagulants in the preservation of blood samples for hematology. A chelating agent, used parenterally in the treatment of lead poisoning. See also edetate. excess calciumin all species may cause hypercalcitonism with decreased osteoclastic activity and skeletal remodeling. In dogs, disorders of enchondral ossification with curved radius and osteochondrosis have been demonstrated; secondary iron deficiency anemia occurs in piglets. calcium fluoridenaturally occurring mineral. Called also fluorspar, fluorite. calcium gelcontains high levels of calcium; given to cows as a drench or in the feed as a prophylaxis against milk fever. calcium gluconatea calcium replenisher and antidote to fluoride or oxalate poisoning. calcium homeostasismaintenance of normal calcium metabolism by the combined effects of adequate alimentary intake, renal excretion, parathyroid hormone involvement, 1,25 dihydroxycholecalciferol (or calcitriol) and calcitonin, plasma protein binding and deposition in tissues. calcium hydroxidean astringent compound used topically in solution or lotions; in dentistry used to encourage deposition of secondary dentine. Called also slaked lime. In solution, called lime water. idiopathic calcium phosphate depositionthought to be inherited as an autosomal dominant trait in Great Danes commencing in puppies about 5 weeks old, characterized by incoordination with deformity and displacement of the 7th cervical vertebra and mineral deposits in the intervertebral joints, in serous and synovial membranes and mineralization in most other tissues. calcium lactateused for supplementing the diet with calcium; contains 18% calcium. As calcium sodium lactate, containing 8% calcium, it is more soluble and can be used in drinking water. calcium levulinatea calcium compound used parenterally in the treatment of hypocalcemia; contains 14.8% calcium. calcium mandelateadministered orally and used as a urinary antiseptic. calcium nitrateused as an additive during cheese making to control fermentation. Whey from this cheese may cause nitrate poisoning in pigs. nondiffusible calciumprotein-bound fractions of plasma calcium. calcium nutritional deficiencynutritional deficiency of calcium is rarely primary except in carnivores on an all-meat diet. Secondary deficiency is usually the result of diets having too high a content of phosphorus. The outcome of either deficiency may be nutritional hyperparathyroidism, rickets, osteomalacia, osteodystrophy in horse and pigs, and degenerative arthropathy of cattle, depending on the species, age of the animal and availability of vitamin D. Hypocalcemia may not occur because of the activity of parathyroid hormone, but classical tetany and recumbency can occur if the deficiency is prolonged or if they are precipitated by some other factor. calcium oxalatea compound occurring in the urine in crystals and in certain calculi. See also oxalate urolith. calcium oxidealkaline and capable of causing gastroenteritis. There is a high concentration in basic slag and this may contribute to that poisoning. calcium pantothenatea calcium salt of the dextrorotatory isomer of pantothenic acid; used as a growth-promoting vitamin. calcium phosphateone of three salts containing calcium and the phosphate radical: dibasic and tribasic calcium phosphate are used as sources of calcium; monobasic calcium phosphate is used in fertilizer and as a calcium and phosphorus supplement. An important constituent of uroliths. calcium : phosphorus ratiothe ratio of calcium to phosphorus in the diet, 1 : 1 to 1 : 2 is usually considered to be adequate for proper calcium nutritional status in most animal species. Diets outside this range are likely to cause osteodystrophies. Animals grazing phosphorus-deficient pasture, and those being intensively fed on grain rations which have an abnormally high phosphorus content, are the principal subjects. Horses on heavy grain diets and dogs and cats on meat diets without calcium supplementation are also targets for the disease. calcium polycarbophila hydrophilic agent used as a bulk laxative in the treatment of constipation and diarrhea. protein bound calciumbiologically inert fraction of plasma calcium; most is bound to albumin and globulins with a small fraction complexed to organic and inorganic acids. calcium silicophosphatecrystals of this mineral are thought to contribute physically to the gastroenteritis caused by basic slag poisoning. calcium sulfatethe main component of plaster of Paris; also used as a dietary source of calcium and inorganic sulfate sulfur. calcium sulfide, calcium polysulfidelime-sulfur. calcium supplementsinclude calcium carbonate, gluconate, lactate and phosphate; bone flour, bone meal, ground limestone, chalk. calcium tungstate screenscards coated with calcium tungstate crystals are used to sandwich film in a light-tight cassette. They fluoresce when exposed to x-rays and, together with the beam, affect the film emulsion. They reduce the exposure factor required. urinary calciumcalciuria.
calcium carbonateAdcal (UK), Alka-Mints, Cacit (UK), Calcarb 600, Calci-Chew, Calci-Mix, Caltrate 600, Children's Pepto Chooz, Florical, Maalox Regular Chewable, Mylanta Children's, Nephro-Calci, Nu-Cal (CA), Os-Cal, Os-Cal 500, Oysco, Oyst-Cal 500, Oystercal 500, Rap-eze (UK), Remegel (UK), Rennie Soft Chews (UK), Rolaids Calcium Rich, SeapCal (UK), Setlers (UK), Tums, Tums E-X, Tums Ultra Pharmacologic class: Mineral Therapeutic class: Dietary supplement, electrolyte replacement agent Pregnancy risk category C (calcium acetate, chloride, glubionate, gluceptate, phosphate), NR (calcium carbonate, citrate, gluconate, lactate) ActionIncreases serum calcium level through direct effects on bone, kidney, and GI tract. Decreases osteoclastic osteolysis by reducing mineral release and collagen breakdown in bone. AvailabilityCalcium 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 glubionate - Syrup: 1.8 g/5 ml (contains 115 mg of elemental calcium) Calcium gluceptate - Injection: 22% solution Calcium gluconate - Injection: 10% solution Tablets: 500 mg, 650 mg, 975 mg Calcium lactate - Tablets: 325 mg, 500 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 PrecautionsUse cautiously in:
• renal insufficiency, pernicious anemia, heart disease, sarcoidosis, hypercrenal 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. | Route | Onset | Peak | Duration | | P.O. | Unknown | Unknown | Unknown | | I.V. | Immediate | Immediate | 0.5-2 hr |
Adverse reactionsCNS: 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 ) InteractionsDrug-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.
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