- See:
-
abnormalities associated w/ vit D;
-
general discussion of vit D:
- Discussion:
- action of l,25-vitamin D3 is to increase absorption of Ca from intestinal tract;
- 1,25 Vit D is known mediator of bone resorption thru indirect action on
osteoclasts;
- amount of this metabolite in circulation is regulated by
parathyroid hormone;
- malfunctions involving this metabolite are a major cause of
metabolic bone dz;
- Dosage:
- most potent metabolite of vitamin D available;
- used for hypocalcemia secondary to chronic renal dialysis, post surgical and idiopathic
hypoparathyroidism;
- dialysis patients:
- initial dose is 0.25ug/day; may increase dosage by 0.25ug/day at 4-8 week intervals if needed;
- max dose: 100 mcg qd (available as 20 and 50 mcg);
- hypoparathyroidism: initial dose is 0.25ug/day given AM;
- may increase dose at 2-4 week intervals;
- contraindicated w/: hypercalcemia, evidence of vit D toxicity;
- must monitor calcium levels frequently;
- caution w/ digitalis (w/ hypercalcemia) and attempt to maintain good fluid intake;
- note: when Vit D is measured in units it is in the non hydroxylated form, and when it is measured
in micrograms (Rocaltrol) it is in the hydroxylated form (1,25 Vit D);
