Diuretics

Question 1

How do mercuric compounds work?

Answer 1

Inhibit sodium reabsorption in proximal tubules

no longer used due to adverse effects

Question 2

How do osmotic diuretics work?

Answer 2

prevent reabsorption of sodium and water from proximal tubule

Question 3

What is an adverse affect of an osmotic diuretic?

Answer 3

Can cause rapid shift of fluid from interstitial compartment to vascular compartment, causing pulmonary edema or increased cardiac workload

Question 4

What is mannitol used to treat? How is it administered?

Answer 4

Cerebral edema and elevated ICP

Not absorbed in G.I. tract – must be given IV

Question 5

Give the equation for central perfusion pressure

Answer 5

CPP = MAP - ICP

Question 6

Who commonly uses glycerin as a diuretic?

Answer 6

Weightlifters swallow glycerin to decrease water weight due to osmotic diuretic effect

Question 7

What are aquaretics? Give an example

Answer 7

ADH receptor blockers that increase urine production (Demeclocycline)

Question 8

What kind of drug can be used to treat patients with SIADH?

Answer 8

Demeclocycline

Question 9

Which patients commonly have SIADH?

Answer 9

Neuro patients with head trauma/increased ICP

Question 10

What were the first diuretics used?

Answer 10

Mercury containing compounds

Question 11

How do you carbonic anhydrase inhibitors work?

Answer 11

They inhibit reabsorption of bicarbonate, causing bicarb waste and water waste

Question 12

What is a potentially serious adverse reaction of carbonic anhydrase inhibitors?

Answer 12

Hypokalemia due to additional waste of potassium

Question 13

What are carbonic anhydrase inhibitors mainly used for?

Answer 13

Management of glaucoma – lower intraocular pressure by decreasing aqueous humor production

Question 14

Why can carbonic anhydrase inhibitor’s affect excretion of other drug products?

Answer 14

Changes in the blood and urine pH alter excretion of drugs

Question 15

What drugs do carbonic anhydrase inhibitors cross react with?

Answer 15

Sulfonamides- can cause rash

Question 16

Which diuretic can be used to treat altitude sickness?

Answer 16

Carbonic anhydrase inhibitors – hemoglobin discharges oxygen for increased consumption if blood becomes acidotic (potential effect of CAIs)

Question 17

What is the only CAI on the market?

Answer 17

Acetazolamide (Diamox)

Question 18

How do thiazides work?

Answer 18

Prevent reabsorption of sodium and water at the distal tubule

Question 19

What is the minimum creatinine clearance at which thiazides can be used?

Answer 19

30 mL per minute

Question 20

What diuretic should be used in cases of reduced CrCl?

Answer 20

Loop diuretics

Question 21

List five electrolyte related side effects of thiazides

Answer 21

Hypokalemia, hypomagnesemia, hyperuricemia, hyperglycemia, hypercalcemia

Question 22

Which patients should not take thiazides?

Answer 22

Patients with gout due to thiazide causing increased uric acid production

Question 23

How quickly do thiazides take effect?

Answer 23

1 to 2 hours

Question 24

Which type of diuretics cause photosensitivity?

Answer 24

Thiazide – patient should wear sunscreen with at least 15 SPF

Question 25

Why are diuretics extra helpful in postmenopausal women?

Answer 25

They cause calcium retention, slowing osteoporosis

Question 26

What time of day should thiazides be taken?

Answer 26

Best in morning, no later then 1700 (5:00)

Question 27

What is the most common thiazide used?

Answer 27

HCTZ

Question 28

Which diuretics are known as high ceiling diuretics and high efficacy diuretics?

Answer 28

Loop diuretics

Question 29

Which type of loop diuretics are more potent and bioavailable?

Answer 29

Bumetanide (#1) and torsemide (#2) (2-4x more effective then furosemide)

Question 30

How do Loop diuretics work?

Answer 30

They block sodium rehab sorption in the loop of Henle

Question 31

How can ototoxicity be prevented in administration of Loop diuretics?

Answer 31

Administer slowly over 2 to 3 minutes to avoid ringing in ears

Question 32

List the two potassium sparing diuretics

Answer 32

Aldosterone antagonists and nonsteroidal potassium sparing diuretics

Question 33

How do aldosterone antagonists work?

Answer 33

They antagonize aldosterone's actions: aldosterone Binds to receptors in the distal tubules to stimulate reabsorption of sodium and water and potassium excretion

Question 34

Must be present for Spironolactone to be effective?

Answer 34

Aldosterone – patient must have functional adrenal gland

Question 35

List two potential side effects of aldosterone antagonists

Answer 35

Hyperkalemia and gynecomastia

Question 36

List four uses of Spironolactone

Answer 36

Hypertension, hirtuism, primary aldosteronism, cirrhosis

Question 37

Why should salt substitutes be avoided when taking aldosterone antagonists?

Answer 37

Salt substitutes often contain potassium rather than sodium and can contribute to hyperkalemia

Question 38

Which diuretic is better for patients with gout?

Answer 38

Aldosterone antagonists

Question 39

Name the Second generation aldosterone antagonist with reduced affinity for estrogen receptors

Answer 39

Eplerenone (Inspra)

Question 40

How do nonsteroidal potassium sparing diuretics work?

Answer 40

Exact mechanism unknown, but affect reabsorption of sodium from the distal tubule

Question 41

Which diuretics are considered low efficacy?

Answer 41

Potassium sparing

Question 42

What are three electrolyte related side effects of nonsteroidal potassium sparing diuretics?

Answer 42

Hyperkalemia, hypercalcemia, hypomagnesemia

Question 43

List two Nonsteroidal potassium sparing diuretics often found in combination with HCTZ

Answer 43

Triamterene and amiloride

Question 44

List five treatments for hyperkalemia in order of ascending strength

Answer 44

Potassium wasting diuretic, SPS (Kayexalate), bicarbonate, insulin with D5W, calcium chloride

Question 45

What is the fastest that potassium should be replaced?

Answer 45

No faster than 10 mEq per hour

Question 46

Which osmotic diuretic is shown to reduce cerebral edema and manage elevated ICP?

Answer 46

Mannitol