Calcitriol + Calcium
Indications
Calcitriol + Calcium is used for:
Osteoporosis, Hypoparathyroidism, Hypocalcaemia, Osteomalacia rickets, Renal osteodystrophy, Chronic kidney dialysis
Adult Dose
Adult: PO Hyperparathyroidism in renal failure 0.25 mcg/day or alternate day. May increase slowly.
Hypoparathyroidism/pseudohypoparathyroidism 0.5-2 mcg once daily.
Vit D-dependent rickets 0.015-0.02 mcg/kg/day.
Maintenance: 0.03-0.06 mcg/kg/day. Max: 2 mcg/day.
Child Dose
Renal Dose
Administration
Contra Indications
Hypercalcaemia; evidence of vitamin D toxicity. Pregnancy (dose exceeding RDA). Lactation.
Precautions
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.
Pregnancy-Lactation
Interactions
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.
Calcitriol : 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.
Adverse Effects
Side effects of Calcitriol + Calcium :
Weakness; headache; somnolence; nausea; vomiting; dry mouth; constipation; muscle pain; bone pain; metallic taste; polyuria; polydipsia; anorexia; irritability; weight loss; nocturia; mild acidosis; reversible azotemia; generalized vascular calcification; nephrocalcinosis; conjunctivitis (calcific); pancreatitis; photophobia; rhinorrhoea; pruritus; hyperthermia; decreased libido; elevated BUN; albuminuria; hypercholesterolaemia; elevated AST and ALT; ectopic calcification; hypertension; cardiac arrhythmias.
Mechanism 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.
Calcitriol 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.