Diuretics

Question 1

overall MOA of diuretics

Answer 1

• act directly on nephron to limit H2O and Na+ reabsorption
• increases excretion of Na+ and H2O by kidneys
• increases amt of urine formed
• decreases BV

Question 2

overall indication of diuretics

Answer 2

HTN
(these are the recommended initial therapy)
cheap!

Question 3

loop diuretic MOA

Answer 3

• act primarily on ascending limb of loop Henle

- inhibits reabsorption of Na+/K+/2Cl- which prevents reabsorption of H2O

Question 4

loop diuretic indication

Answer 4

• Strong diuretic

- Moderate antihypertensive

Question 5

loop diuretic AE

Answer 5

dehydration, hypokalemia, hyponatremia, hypocalcemia, ototoxicity, hyperglycemia, increased LDLs

Question 6

What loop diuretic drug names should we be familiar with?

hint: froot loops

Answer 6

furosemide (Lasix)

think of “Froot Loops” cereal: froot = furo and loops = loop diuretic

Question 7

thiazide diuretic MOA

Answer 7

• Act on early part of distal convoluted tubules
• Inhibit mechanisms that favor Na+ reabsorption
• result in Na+ & K+ excretion and reabsorption of Ca+

Question 8

thiazide diuretic indication

Answer 8

• powerful antihypertensive, moderate diuretic

- lowers systolic BP > than other antiHTN drugs

Question 9

why are thiazide diuretics favored for older adults?

Answer 9

to reduce Ca+ loss and maintain bone mass

Question 10

why are thiazide diuretics the most frequently used diuretics?

Answer 10

• Prime choice for HTN
• May be given along with loop diuretics in cases of CHF and severe edema
• Better choice for individuals prone to renal calculi (kidney stones)

Question 11

thiazide diuretic AE

Answer 11

• similar to loop diuretics

- thiazide diuretics can also cause hypercalcemia and significant K+ loss

Question 12

What thiazide diuretic drug names should we be familiar with?

hint: has “thiazide” at the end of the name

Answer 12

Hydrochlorothiazide (HCTZ)

Question 13

Potassium-sparing diuretic MOA

Answer 13

• interferes with and inhibits Na+/K+ exchange mechanism in the late distal convoluted tubules
• limits reabsorption of Na+ and excretion of K+
• limits the osmotic gradient which drives the reabsorption of H2O from tubule
• prevents hypokalemia

Question 14

Potassium-sparing diuretic indication

Answer 14

• Less effective at producing diuresis

- Treats HTN

Question 15

Potassium-sparing diuretic AE

hint: KLMN

Answer 15

hyperkalemia, lethargy, mental confusion, nausea

Question 16

What potassium-sparing diuretic drug names should we be familiar with?

Hint: If you’re a male, you want to spare yourself from lactating

Answer 16

• spironolactone

- AE: blocks aldosterone receptor which produces gynecomastia in males and menstrual irregularities in females

Question 17

therapeutic concerns with diuretics

Answer 17

• Be alert for signs of hypokalemia or hyperkalemia
• May produce hyperglycemia and abnormal lipid levels
• Fluid depletion/dehydration (can result in significant confusion in the elderly)
• OH (can lead to falls)
• arrhythmias
• DDIs with NSAIDS

Question 18

what DDI can occur between diuretics and NSAIDs?

Answer 18

NSAIDs cause Na+ retention and decrease in renal perfusion -> make diuretics less effective