Drugs and the Kidney

Question 1

Tubular secretion of drugs is independent of protein binding. T/F?

Answer 1

True

Question 2

Glomerular filtration of drugs depends on GFR and protein binding. T/F?

Answer 2

True

Question 3

Weak acids are more easily secreted into urine of what pH?

Answer 3

Alkaline pH

Question 4

Why are lipid soluble drugs not excreted to any great extent in the urine?

Answer 4

They are passively reabsorbed by diffusion across the tubule

Question 5

In which part of the kidney tubule are weak acid drugs most actively secreted?

Answer 5

PCT

Question 6

Which formula is used to calculate a drug dose in light of impaired GFR?

Answer 6

Cockcroft Gault formula

Question 7

What effect does chronic kidney disease have an the metabolism of drugs such as CNS depressants and antihypertensives?

Answer 7

Increased sensitivity to these drugs

Question 8

What effect does chronic kidney disease have an the metabolism of drugs such as diuretics and urinary antibacterials?

Answer 8

Reduced sensitivity to these drugs

Question 9

Why is the increased sensitivity to opiates in patients with impaired renal function significant?

Answer 9

It causes significant respiration depression

Question 10

Give examples of some drugs which have enhanced adverse effects in the presence of chronic kidney disease?

Answer 10

Digoxin
Potassium-sparing diuretics
Biguanides
Sulphonylureas

Question 11

Reduced excretion of drugs due to chronic kidney disease leads to enhanced toxicity. Give example of drugs for which this is a problem?

Answer 11

Opiates / CNS depressants
Aminoglycosides
Digoxin
Aciclovir

Question 12

When is dose adjustment in renal failure required?

Answer 12

When the drug has at least a 50% renal clearance and a low therapeutic index

Question 13

Give examples of some drugs whose dose needs adjusted in renal failure?

Answer 13

Aminoglycosides
Lithium
Amphotericin
Metofrmin
ACE inhibitors
Methotrexate

Question 14

What are the ideal qualities of a drug for use in patients with renal failure?

Answer 14

Predominately secreted by liver
<25% excretion unchanged
No active metabolites
Wide therapeutic index
Disposition unaffected by protein binding or fluid balance changes
Response unaffected by tissue sensitivity changes
Not nephrotoxic

Question 15

How can NSAID use result in acute kidney injury?

Answer 15

The prostaglandins produced by these drugs can cause afferent arteriole dilation and an increase in GFR

Question 16

Give examples of drugs which can cause acute tubular necrosis?

Answer 16

Aminoglycosides
Amphotericin B
Cisplatin
NSAIDs
Radiocontrast media
Paracetamol

Question 17

Give examples of drugs which can cause renal tubular acidosis?

Answer 17

Acetaxolamide
Amphotericin B
lithium

Question 18

Give examples of drugs which can cause interstitial nephritis?

Answer 18

Allopurinol
Azathioprine
Frusemide
NSAIDs
Penicillins
Sulphonamides
Thiazides
Vancomycin

Question 19

Give examples of drugs which can cause nephrotic diabetes insipidus?

Answer 19

Lithium

Demeclocycline

Question 20

Give examples of drugs which can cause renal papillary necrosis?

Answer 20

Aspirin

NSAIDs

Question 21

What are some of the generic causes of nephrotoxicity?

Answer 21

Pre-renal acute kidney injury
Glomerular damage
Tubular damage
Ureteric obstruction

Question 22

What is the presentation of nephrotoxicity?

Answer 22

Acute kidney injury
Chronic renal failure
Nephrotoxic syndrome
Lupus-like syndrome
Nephrogenic diabetes insipidus
Fluid overload
Uraemia

Question 23

Give examples of loop diuretics

Answer 23

Bumetanide

Furosemide

Question 24

Give an example of a thiazide diuretic

Answer 24

Bendroflumethazide

Question 25

Give an example of a potassium sparing diuretic?

Answer 25

Spironolactone

Question 26

What part of the nephron is the site of action of a loop diuretic?

Answer 26

Thick ascending loop of Henle

Question 27

What part of the nephron is the site of action of a thiazide diuretic?

Answer 27

Cortical DCT

Question 28

What part of the nephron is the site of action of a potassium sparing diuretic?

Answer 28

Distal DCT and collecting duct

Question 29

What is the clinical use of loop diuretics?

Answer 29

Odema
Acute renal failure
Hypertension
Hypercalcaemia

Question 30

What is the clinical use of thiazide diuretics?

Answer 30

Hypertension
Oedema
Hypercalcaemia
Nephrogenic diabetes insipidus

Question 31

What is the clinical use of potassium sparing diuretics?

Answer 31

Potassium conservation
Oedema
Hyperaldosteronism
Hypertension

Question 32

Loop diuretics can cause ototoxicity in high doses.T/F?

Answer 32

True

Question 33

Which transporter do loop diuretics work on?

Answer 33

The sodium/potassium/2chloride transporter

Question 34

What is the action of amiloride?

Answer 34

A sodium channel blocker - blocks the ENaC channel in the collecting duct

Question 35

What are the potential side-effects of thiazide and loop diuretics?

Answer 35

Non-specific GI upsets
Hypersensitivity reactions
Metabolic effects (hypokalaemia, rate retention, glucose intolerance)
Ototoxicity

Question 36

Glomerular filtration will filter non-protein bound drugs of a molecular weight below…?

Answer 36

20kDa

Question 37

What is the name of the type of transporter which aids the secretion of acidic drugs?

Answer 37

Organic anion transporter (OAT)

Question 38

What is the name of the type of transporter which aids the secretion of acidic drugs?

Answer 38

Organic cation transporter (OCT)

Question 39

Carrier-mediated transport in the secretion of drugs in the kidney tubule can achieve maximal drug clearance even when most of the drug is bound to plasma proteins. T/F?

Answer 39

True

Question 40

How can one drug affect the rate of renal excretion of another drug?

Answer 40

By altering protein binding and hence altering filtration of the drug
Inhibiting tubular secretion of the drug
Altering urine flow and/or pH