Drug Dosing and CKD

Question 1

The Cockcroft-Gault Equation

Answer 1

CrCl (male) = (140-age) x weight (kg)
72 x SCr (mg/dL)
CrCl (female) = 0.85 x male CrCl

Question 2

The Cockcroft-Gault Equation Weight is ideal body weight (unless actual is less)

Answer 2

Male 50.0 kg + 2.3kg per inch over 5 feet

Female 45.5kg + 2.3kg per inch over 5 feet

Question 3

Nephrotoxic agents

Answer 3

NSAIDs:  Why is this one so big?
Aminoglycosides
Heavy metals (lead, gold compounds, mercury)
Radiocontrast (iodide compounds)
Ethylene glycol (antifreeze)

Question 4

What Drug induce seizures at high concentrations

Answer 4

Imipenem

Question 5

What to achieve with Maintenance doses

Answer 5

In the absence of a loading dose, maintenance doses will achieve 90% of their steady-state level in 3.3 half lives

Question 6

when modification is not necessary

Answer 6

GFR’s >50

Question 7

Drugs that should be avoided in severe kidney disease

Answer 7

Metformin (Glucophage) (high risk of lactic acidosis)
Aspirin, NSAIDs (may worsen decrease in GFR)
Spironolactone (K+ accumulation)
Thiazide diuretics (HCTZ) (not effective)

Question 8

drugs where no dosage adjustment is required with chronic kidney disease:

Answer 8

Azithromycin (Zithromax)
Ceftriaxone (Rocephin)
Moxifloxacin (Avelox)
Doxycycline (Vibramycin)

Question 9

The MDRD equation

Answer 9

Very useful and frequently used approach in calculating CrCl based on SCr