Indication

Osteoporosis, Hypoparathyroidism, Hypocalcaemia, Osteomalacia rickets, Renal osteodystrophy, Chronic kidney dialysis

Adult Dose

PO \r\nAdult: 1 tablet twice daily.\r\nHyperparathyroidism in renal failure 0.25 mcg/day or alternate day. May increase slowly. \r\nHypoparathyroidism/pseudohypoparathyroidism 0.5-2 mcg once daily. \r\nVit D-dependent rickets 0.015-0.02 mcg/kg/day. \r\nMaintenance: 0.03-0.06 mcg/kg/day. Max: 2 mcg/day. \r\n

Contraindication

Hypercalcaemia; evidence of vitamin D toxicity. Pregnancy (dose exceeding RDA). Lactation.

Mode of Action

Calcium salt can be used in the prevention and treatment of calcium deficiency states or negative calcium balance. It is also used as an adjunct in the prevention and treatment of osteoporosis.\r\n\r\nCalcitriol promotes calcium absorption in the intestines and retention at the kidneys thus increasing serum calcium levels. It also increases renal tubule phosphate resorption consequently decreasing serum phosphatase levels, PTH levels and bone resorption.\r\n

Precaution

Idiopathic hypercalcaemia. Pediatric doses must be individualised and monitored under close medical supervision. Coronary disease, renal function impairment and arteriosclerosis, especially in the elderly. Hypoparathyroidism.

Side Effect

Calcium \r\nAnorexia, Constipation, Flatulence, Nausea, Vomiting, Hypercalcemia, Hypophosphatemia, Xerostomia, Acid rebound, Milk-alkali syndrome, Coma, Confusion, Delirium, Headache, Lethargy.\r\n\r\nCalcitrol:\r\nAbdominal pain,Apathy,BUN and creatinine increased,Cardiac arrhythmia,Constipation,Dry mouth,Dehydration,Growth suppression,Headache,Hyperthermia,Hypercalcemia,Hypercholesteremia,Hypermagnesemia,Hyperphosphatemia,Hypertension,Libido decreased,Metallic taste,Muscle or bone pain,Nocturia,Pruritus,Psychosis,Somnolence,Weakness

Pregnancy Category Note

Pregnancy category: C\r\n\r\nLactation: Enters breast milk; not recommended

Interaction

Calcium: Co-administration with thiazide diuretics or vit D may lead to milk-alkali syndrome and hypercalcaemia. Decreased absorption with corticosteroids. Decreases absorption of tetracyclines, atenolol, iron, quinolones, alendronate, Na fluoride, Zn and calcium-channel blockers. Enhances cardiac effects of digitalis glycosides and may precipitate digitalis intoxication.\r\n\r\n\r\nCalcitriol : Hypermagnesaemia may develop in patients on chronic renal dialysis. Hypercalcaemia in patients on digitalis may precipitate cardiac arrhythmias. Intestinal absorption of calcitriol may be reduced by cholestyramine and colestipol. Phenytoin, barbiturates may decrease the T1/2 of calcitriol. May develop hypercalcaemia with thiazide diuretics.