CALCIFEDIOL
(kal-si-fe-dye'ole)
Calderol
Classifications: hormone and synthetic substitute; vitamin d analog
Prototype: Calcitriol
Pregnancy Category: C

Availability

20 mcg, 50 mcg capsules

Actions

Vitamin D analog and major transport form of cholecalciferol (D3) Vitamin D analog is fat soluble. Because it is activated in the body and has regulatory effects, it is considered a hormone. Primary action leads to regulation of serum calcium, which is affected also by the activity of other vitamin D analogs (e.g., ergocalciferol), parathyroid hormone, and calcitonin. Pharmacologic effects of calcifediol are related to its intrinsic vitamin D activity as well as to the properties of active metabolites (e.g., calcitriol), which result from renal metabolism.

Therapeutic Effects

Helps to maintain serum calcium in patients undergoing chronic renal dialysis and effective in renal osteodystrophy and promotes healing in hepatic osteomalacia.

Uses

Management of metabolic bone disease and hypocalcemia associated with chronic renal failure in patients undergoing renal dialysis.

Unlabeled Uses

Osteopenia caused by prolonged glucocorticoid therapy and osteomalacia secondary to hepatic disease.

Contraindications

Hypersensitivity to vitamin D, vitamin D toxicity, hypercalcemia. Safe use of doses in excess of RDA during pregnancy (category C), lactation, and children not established.

Cautious Use

Patients receiving digitalis glycosides.

Route & Dosage

Metabolic Bone Disease in Patients With Chronic Renal Failure
Adult: PO Initially 300–350 mcg/wk administered on a daily or alternate day schedule, may increase at 4-wk intervals if necessary; patients with normal calcium may only need 20 mcg q.o.d. (usual range 50–100 mcg/d or 100–200 mcg q.o.d.)

Administration

Oral

Adverse Effects (1%)

Body as a Whole: Muscle or bone pain, idiosyncratic reaction (headache, nausea, vomiting, diarrhea, fever). GI: Anorexia, nausea, vomiting, dry mouth, thirst, constipation, diarrhea, abdominal cramps, metallic taste. Metabolic: Vitamin D intoxication, hypercalcemia, polyuria, hypercalciuria, hyperphosphatemia. CNS: Lethargy, headache, weakness, vertigo.

Interactions

Drug: thiazide diuretics may cause hypercalcemia; may precipitate digitalis arrhythmias with digoxin.

Pharmacokinetics

Absorption: Readily absorbed from small intestines. Peak: 4 h. Duration: 15–20 d. Distribution: Stored chiefly in liver and fat deposits. Metabolism: Activated in kidneys. Elimination: Excreted primarily in bile and feces. Half-Life: 12–22 d.

Nursing Implications

Assessment & Drug Effects

Patient & Family Education


Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug