Pharmacology of CKD Flashcards
As kidney function declines
PO4 increases Inhibited Vit D Increased PTH secretion Calcium is maintained through bone resorption Soft tissue calcification
Goals of CKD Management
Normalize Ca, PO4 Ca X P and PTH
Prevent the progression to renal ostedystrophy CV and extravascular calcification and associated morbidity and mortality
HypoCa =
Less than 8.5
CaXP
Less than 55
PTH range for stage 4 and 5 CKD
Above normal range to prevent over suppression of PTH and reduce risk of adynamic bone disease
Non-pharmacologic therapy
Phosphate restriction to 800-100 mg/d
Dialysis- HD/PD lower serum P and Ca
Parathyroidectomy: for severe CKD-MBD
MOA of Phosphate binding agents
Bind dietary phosphorous in the GI tract and form an insoluble product to be pooped out
Phosphate binding agents include:
Elemental Ca, lanthanum, aluminum and magnesium and nonelemental agent sevelamer carbonate
First line product =
Oral calcium compounds for control of PO4 and Ca
Calcium carbonate
More soluble in acidic environments (before meals)
Calcium acetate
binds 2X more PO4
Sevelamer carbonate
Nonabsorbable, non-elemental hydrogel
Lanthanum carbonate
ESRD pts
Aluminum salts
Restricted to 4 week therapy
Mg containing antacid
Limited in CKD bc of GI side effects and Mg accumulation
Phosphate binding agents ADRs
Gi side effects
Hypercalcemia
CNS toxicity and anemia with Al binders
Hypermg and hyper K with Mg binders
Vit D MOA
Activated Vit D (calcitriol) suppresses PTH secretion by stimulating absorption of Ca by intestinal cells, reabsorption in the proximal tubule and act on the parathyroid gland
Ergocalciferol and Cholecalciferol
Must be converted to active form in kidney
Calcitriol
Most active and available IV or oral
Paricalcitol or doxercalciferol
Analogs of calcitriol
Treatment for pts with severe kidney disease?
Calcitriol or analogs bc they don’t have to be converted
Treatment for hemodialysis pts
IV calcitriol
Treatment for non-hemodialysis pts and peritoneal dialysis pts
Oral calcitriol
Calcimimetics MOA
Acts on the Ca-sensing receptors on the surface of the cief cells of the parathyroid gland to mimic the effect of extracellular Ca and increase the sensitivity of the receptors to Ca
Calcimimetics =
Cinacalcet HCl (Senispar)
Senispar is used for
Treatment of secondary hyperparathyroidism in ESRD pts and hypercalcemia in pts with parathroid carcinoma
Sensipar (Cinacalcet) does NOT
increase intestinal Ca and PO4 absorption
Calcimimetics ADR
N/V
