Calcium Acetate
Calcium Acetate Tablets, USP
FULL PRESCRIBING INFORMATION: CONTENTS*
- Description:
- Clinical Pharmacology:
- Calcium Acetate Indications and Usage:
- Contraindications:
- Warnings:
- Precautions:
- Side Effects:
- Overdosage:
- Dosage and Administration:
- How Supplied:
- PRINCIPAL DISPLAY PANEL - 667 mg Bottle Label
FULL PRESCRIBING INFORMATION
Description:
Each white to off-white, round, biconvex tablet (debossed with "P113" on one face) contains 667 mg calcium acetate, USP (anhydrous; Ca(CH3COO)2; MW = 158.17 grams) equal to 169 mg (8.45 mEq) calcium; polyethylene glycol 8000; and magnesium stearate. Calcium Acetate Tablets, USP are administered orally for the control of hyperphosphatemia in end stage renal failure.
Clinical Pharmacology:
Patients with advanced renal insufficiency (creatinine clearance less than 30 mL/min) exhibit phosphate retention and some degree of hyperphosphatemia. The retention of phosphate plays a pivotal role in causing secondary hyperparathyroidism associated with osteodystrophy, and soft-tissue calcification. The mechanism by which phosphate retention leads to hyperparathyroidism is not clearly delineated. Therapeutic efforts directed toward the control of hyperphosphatemia include reduction in the dietary intake of phosphate, inhibition of absorption of phosphate in the intestine with phosphate binders, and removal of phosphate from the body by more efficient methods of dialysis. The rate of removal of phosphate by dietary manipulation or by dialysis is insufficient. Dialysis patients absorb 40% to 80% of dietary phosphorus. Therefore, the fraction of dietary phosphate absorbed from the diet needs to be reduced by using phosphate binders in most renal failure patients on maintenance dialysis. Calcium acetate, when taken with meals, combines with dietary phosphate to form insoluble calcium phosphate which is excreted in the feces. Maintenance of serum phosphorus below 6.0 mg/dl is generally considered as a clinically acceptable outcome of treatment with phosphate binders. Calcium Acetate Tablets, USP are highly soluble at neutral pH, making the calcium readily available for binding to phosphate in the proximal small intestine.
Orally administered calcium acetate from pharmaceutical dosage forms has been demonstrated to be systemically absorbed up to approximately 40% under fasting conditions and up to approximately 30% under nonfasting conditions. This range represents data from both healthy subjects and renal dialysis patients under various conditions.
Indications and Usage:
Calcium Acetate Tablets, USP are indicated for the control of hyperphosphatemia in end stage renal failure and does not promote aluminum absorption.
Contraindications:
Patients with hypercalcemia.
Warnings:
Patients with end stage renal failure may develop hypercalcemia when given calcium with meals. No other calcium supplements should be given concurrently with Calcium Acetate Tablets, USP.
Progressive hypercalcemia due to overdose of Calcium Acetate Tablets, USP may be severe as to require emergency measures. Chronic hypercalcemia may lead to vascular calcification, and other soft-tissue calcification. The serum calcium level should be monitored twice weekly during the early dose adjustment period.
The serum calcium times phosphate (CaXP) product should not be allowed to exceed 66.Radiographic evaluation of suspect anatomical region may be helpful in early detection of soft tissue calcification.
Precautions:
General:
Excessive dosage of Calcium Acetate Tablets, USP induces hypercalcemia; therefore, early in the treatment during dosage adjustment serum calcium should be determined twice weekly. Should hypercalcemia develop, the dosage should be reduced or the treatment discontinued immediately depending on the severity of hypercalcemia. Calcium Acetate Tablets, USP should not be given to patients on digitalis, because hypercalcemia may precipitate cardiac arrhythmias. Calcium Acetate Tablets, USP therapy should always be started at low dose and should not be increased without careful monitoring of serum calcium. An estimate of daily calcium intake should be made initially and the intake adjusted as needed. Serum phosphorus should also be determined periodically.
Information for the patient:
The patient should be informed about compliance with dosage instructions, adherence to instructions about diet and avoidance of the use of nonprescription antacids. Patients should be informed about the symptoms of hypercalcemia (see ADVERSE REACTIONS section).
Drug Interactions:
Calcium Acetate Tablets, USP may decrease the bioavailability of tetracyclines.
Carcinogenesis, Mutagenesis, Impairment of Fertility:
Long term animal studies have not been performed to evaluate the carcinogenic potential, mutagenicity, or effect on fertility of calcium acetate tablets.
Pregnancy:
Teratogenic Effects:
Category C.
Animal reproduction studies have not been conducted with calcium acetate tablets. It is not known whether calcium acetate tablets can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Calcium acetate tablets should be given to a pregnant woman only if clearly needed.
Pediatric Use:
Safety and effectiveness in pediatric patients have not been established.
Geriatric Use:
Of the total number of subjects in clinical studies of calcium acetate tablets (n= 91), 25 percent were 65 and over, while 7 percent were 75 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.
Side Effects:
In clinical studies, patients have occasionally experienced nausea during calcium acetate tablet therapy. Hypercalcemia may occur during treatment with Calcium Acetate Tablets, USP. Mild hypercalcemia (Ca >10.5 mg/dl) may be asymptomatic or manifest itself as constipation, anorexia, nausea and vomiting. More severe hypercalcemia (Ca >12 mg/dl) is associated with confusion, delirium, stupor and coma. Mild hypercalcemia is easily controlled by reducing the Calcium Acetate Tablets, USP dose or temporarily discontinuing therapy. Severe hypercalcemia can be treated by acute hemodialysis and discontinuing calcium acetate tablets therapy.
Decreasing dialysate calcium concentration could reduce the incidence and severity of Calcium Acetate Tablets, USP induced hypercalcemia. The long-term effect of calcium acetate tablets on the progression of vascular or soft tissue calcification has not been determined. Isolated cases of pruritus have been reported which may represent allergic reactions.
Overdosage:
Administration of Calcium Acetate Tablets, USP in excess of the appropriate daily dosage can cause severe hypercalcemia (See ADVERSE REACTIONS ).
Dosage and Administration:
The recommended initial dose of Calcium Acetate Tablets, USP for the adult dialysis patient is 2 tablets with each meal. The dosage may be increased gradually to bring the serum phosphate value below 6 mg/dl, as long as hypercalcemia does not develop. Most patients require 3 to 4 tablets with each meal.
How Supplied:
In tablet form with "P113" debossed on one side and plain on the other, for oral administration. Each white round tablet contains 667 mg calcium acetate (anhydrous; Ca(CH3COO)2; MW = 158.17 grams) equal to 169 mg (8.45 mEq) calcium; polyethylene glycol 8000; and magnesium stearate.
Tablets, NDC 0574-0113-02, bottles of 200.
Storage:
Store at 20 to 25 C (68 to 77 F) [see USP Controlled Room Temperature]
Paddock Laboratories, Inc.
Minneapolis, MN 55427
(02-10)
PRINCIPAL DISPLAY PANEL - 667 mg Bottle Label
NDC 0574-0113-02
CALCIUM ACETATE
TABLETS, USP
667 mg*
Rx ONLY
Take as directed by your physician.
200 TABLETS
Paddock
Laboratories, Inc.
Calcium AcetateCALCIUM ACETATE TABLET
|