(THER) Diuretics Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What does it mean when we say a drug is natriuretic?

A

It increases Na+ excretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

SIte of action for Acetazolamide (and other Carbonic Anhydrase inhibitors)

A

PCT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Site of action for Mannitol (and other osmotic diuretics)

A

PCT, as well as thin descending limb and CT [in presence of ADH])

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Site of action for Furosemide (and others in its class)

A

Thick ascending limb of the loop of Henle

(They are known as loop diuretics)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Site of action for the Thiazides

A

DCT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Site of action for the K+-sparing diuretics

A

CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Site of action for ADH antagonists

A

The CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The primary therapeutic goal of diuretic use is to ________ _________

A

Reduce Edema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Except for __________ and some __________ diuretics generally exert their effects from the _________ side of the nephron.

A

Spironolactone; ADH antagonists; luminal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does mannitol get into the tubule fluid as compared to most of the other diuretics?

A

Mannitol: via filtration at the glomerulus

Others: via secretionacross the proximal tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does carbonic anydrase inhibition cause diuresis?

A

By blocking the function of carbonic anhydrase, you decrease HCO3- reabsorption and therefore increase the amount which makes it to the distal nephron. Na+ is the most abundunt cation present in proximal tubule fluid and thus accompanies HCO3-. At the distal tubule, Na+ is reabsorbed but bicarb holds the water in the tube and you pee it out.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Name the carbonic anhydrase inhibitors (4)

A
  1. Methazolamide
  2. Acetazolamide
  3. Dichlorphenamide
  4. Dorzolamide

Princess is MADD about CA (california)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name the osmotic diuretic (1)

A

Mannitol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Name the Loop Diuretics (4)

A
  1. Furosemide
  2. Bumetanide
  3. Torsemide
  4. Ethacrynic acid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Name the Thiazides (5)

A
  1. Metolazone
  2. Indapamide

Chlorthalidone

  1. Hydrochlorothiazide
  2. Chlorothiazide

MI CHC (chick) has nice Thiaz (thighs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Potassium-sparing Diuretics (4)

A
  1. Amiloride
  2. Triamterene
  3. Eplerenone
  4. Spironolactone

I took a SEAT on my potASSium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name the ADH antagonists (5)

A
  1. Demeclocyline
  2. Lithium
  3. Tolvaptan
  4. Conivaptan
  5. Mozavaptan
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

MOA of Carbonic Anhydrase Inhibitors

A

Inhibit CA in luminal membrane of proximal tubule, reducing proximal HCO3-reabsorption.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

MOA of the Osmotic Diuretics

A

Act primarily on the proximal tubule to reduce the reabsorption of H2O and solutes including NaCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

MOA of the Loop Diuretics

A

Inhibit the Na+/ K+/ 2Cl- cotransport system in the thick ascending limb of Henle’s loop (ALH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

MOA of the Thiazides

A

Inhibit NaCl cotransport in early distal convoluted tubule (DCT).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

MOA of the K+-sparing diuretics (2)

A
  1. Spironolactone & eplerenone competitively block the actions of aldosterone on the collecting tubules.
  2. Amiloride and triamterene reduce Na+ entry across the luminal membrane of the principal cells of the collecting tubules.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

MOA of ADH Antagonists

A

Prevent ADH induced water reabsorption in the principal cells of the collecting tubule.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Main indications for use of Carbonic Anhydrase (3)

A
  1. To reduce intraocular pressure in glaucoma.
  2. To lower [HCO3-]p in “mountain sickness”.
  3. To raise urine pH in cystinuria.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are some other uses for CA Inhibitors other than their main indications? (3)

A
  1. Hypokalemic periodic paralysis.*
  2. Adjunctive therapy in epilepsy.
  3. Solid hypoxic tumors?

PET

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Main indications for Osmotic diuretics

A
  1. To treat or prevent Acute Renal Failure (ARF).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are some other uses for Osmotic Diuretics other than its main one? (2)

A
  1. To reduce intra-cranial or intra-ocular pressure.
  2. To enhance urinary excretion of chemical toxins.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Main Indications for Loop Diuretics (4)

A
  1. Acute Pulmonary Edema.
  2. Hypertension.
  3. Congestive heart failure (CHF)—in the presence of renal insufficiency or for immediate effect).
  4. ARF, CRF, ascites, and nephrotic syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Other use for loop diuretics other than main indication

A

Hyercalcemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Main indications for thiazides (3)

A
  1. Hypertension.
  2. Edema due to CHF, hepatic cirrhosis, renal disease.
  3. Idiopathic Hypercalciuria (renal calculi).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is another use for thiazides other than the main indication?

A

Nephrogenic Diabetes Insipidus (prevent further urine dilution from taking place in the DCT).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Main Indications of K+-Sparing Diuretics (2)

A
  1. Chronic liver disease: to treat secondary hyperaldosteronism due to hepatic cirrhosis complicated by ascites (spironolactone, eplerenone).
  2. To prevent the hypokalemic effects of other diuretics.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Name alternative uses for K+-sparing diuretics. Which specific drugs are involved?

A

Primary hyperaldosteronism (Conn’s syndrome)— spironolactone, eplerenone.

34
Q

Main Indications for ADH Antagonists (2)

A
  1. SIADH
  2. Euvolemic or hypervolemic hyponatremia
35
Q

Name alternative use for ADH antagonist

A

CHF

36
Q

AE of CA Inhibitors (3 main ones)

A
  1. Metabolic acidosis (due to HCO3- depletion with prolonged treatment)
  2. Hypokalemia (acute effect)
  3. Drowsiness, fatigue, CNS depression, and paresthesia.
37
Q

AE of Osmotic Diuretics (4)

A
  1. Acute expansion of ECF volume and increased risk of pulmonary edema
  2. Hhyponatremia (with impaired renal function)
  3. Hypernatremia (prolonged use with normal GFR).
  4. Nausea and vomiting; headache.
38
Q

AE of Loop Diuretics (4 general ones)

A
  1. Hypokalemia hypomagnesemia; hyponatremia; hypovolemia
  2. Hyperuricemia*
  3. Metabolic alkalosis
  4. Ototoxicity and diarrhea (mainly with ethacrynic acid)
39
Q

AE of Thiazides (6)

A
  1. Hypokalemia; hyponatremia; hypovolemia;
  2. Hyperuricemia due to enhanced urate reabsorption* and hypercalcemia due to enhanced Ca2+ reabsorption
  3. Metabolic alkalosis
  4. Hyperglycemia (insulin resistance); hyperlipidemia.
  5. Hypersensitivity (fever, rash, purpura, anaphylaxis);
  6. Interstitial nephritis
40
Q

AE of K+-sparing diuretics (Spironlactone?Amiloride?Triamterene?)

A
  • Spironolactone: hyperkalemia, gynecomastia, hirsutism; menstrual irregularities; testicular atrophy (with prolonged use).
  • Amiloride: hyperkalemia, glucose intolerance in diabetic pts.
  • Triamterene: hyperkalemia; megaloblastic anemia in pts with liver cirrhosis.

HYPERKALEMIA

41
Q

AE of ADH Antagonists (which drugs have which effects?)

A
  • Lithium, doxycycline: nephrotoxic
  • Tolvaptan, conivaptan, mozavaptan: hypernatremia, thirst, dry mouth, hypotension, dizziness
42
Q

ACE inhibitors interact with which diuretics? What can occur as a result?

A

K+-sparing diuretics

Increaed hyperkalemia and resultant cardiac arrhythmias

43
Q

Aminoglycosides interact with which diuretics? What can occur as a result?

A

Loop diuretics

Ototoxicity and nephrotoxicity

44
Q

Anticoagulants interact with which diuretics? What can occur as a result?

A

Thiazide and Loop diuretics

Increased anti-coagulant activity with loop

Decreased anti-coagulant activity with thiazide

45
Q

B-blockers interact with which diuretics? What can occur as a result?

A

Thiazide and Loop Diuretics

Hyper- glycemia, lipidemia, uricemia

Increased plasma levels of propanolol

46
Q

Carbamazepine/ chloropropamide interact with which diuretics? What can occur as a result?

A

Thiazide diuretics

Increased risk of hyponatremia

47
Q

Digoxin interacts with which diuretics? What can occur as a result?

A

Thiazide and Loop diuretics

Hyopokalemia and increaed digoxin binding/toxicity

48
Q

NSAIDs interact with which diuretics? What can occur as a result?

A

Thiazide and Loop Diuretics/ K+ sparing diuretics

Reduced diuretic effect. Increaed risk of salicylate toxicity with high doses of salicylates (thiazide/ loop d.)

Increased risk of hyperkalemia (K+ sparing d.)

49
Q

Quinidine interacts with which diuretics? What can occur as a result?

A

Loop and thiazide d.

Polymorphic V. Tach (torsade de pointes)

50
Q

Sulfonylureas interact with which diuretics? What can occur as a result?

A

Loop diuretics

Hyperglycemia

51
Q

Steroids interact with which diuretics? What can occur as a result?

A

Thiazide and Loop d.

Increased risk of hypokalemia

52
Q

Contraindication for acetazolamide

A

Cirrhosis (increased urine pH reduces NH3 secretion and thereby increases serum NH3)

53
Q

What are the difference in the (4) CA Inhibitors

A
  • Dichlorphenamide: about 30x more potent than acetazolamide
  • Methazolamide: about 5x more potent than acetazolamide
  • Dorzolamide: topical preparation for ocular use (no systemic effects)
54
Q

Mannitol route

A

IV

55
Q

Contraindications for Mannitol

A
  1. CHF
  2. Renal failure
  3. Pulmonary edema
56
Q

How does K+ in the lumen of the nephron affect diffusion of other positvely charged ions?

A

The positive charge repels the Ca2+ and Mg2+, increasing their paracellular diffusion and reabsorption.

57
Q

What is the most efficacious diuretic class?

A

Loop diuretics

They can cause excretion of up to 20% of the filitered Na+

58
Q

Which diuretics are the only ones which cause vasodilation?

A

Loop diuretics

59
Q

Which diuretic is the only one to cause otoxicity?

A

Loop diuretics

(furosemide)

60
Q

Key points about Bumetanide

A

Loop diuretic

–About 40X more potent than furosemide

–Shorter half-life than furosemide: ~ 1 hr

–50% metabolized by the liver

61
Q

Key points about torsemide

A

Loop diuretic

–Longer half-life than furosemide: ~ 3 hrs

–Longer duration of action, too: ~ 5-6 hrs

–Better oral absorption than furosemide

–80% metabolized by the liver

62
Q

Key points about ethacrynic acid

A

Loop Diuretic

Last resort; used only when others exhibit hypersensitivity

–No CA inhibition

–Nephrotoxic and ototoxic

63
Q

What AE are unique to thiazides?

A

Hyperglycemia and hyperlipidemia

64
Q

How do thiazides prevent kidney stones?

A

By reducing ca2+ excretion

65
Q

What is the most efficacious thiazide? It is the only one used if pt has ________ _________

A

Metolazone. Only one used if pt has renal insufficiency.

66
Q

How is Amiloride secreted into the nephron?

A

Via the organic base transporter

67
Q

Difference between amiloride and triamterene

A

Triamterene is 10x less potent than amiloride and has a shorter half-life

68
Q

Which ADH antagonists affect which vasopressin receptors?

A

V2 receptor antagonists: tolvaptan, mozavaptan, and lixivaptan

V1a and V2 receptor antagonist: conivaptan

69
Q

Combination of what (2) diuretics will cause a powerful urination of Na+ (and as such can be a powerful diuresis)?

A

Loop and thiazides

70
Q

Edema associated with hepatic cirrhosis is resistant to what type of diuretics? Which are effective?

A

Resistant to loop

Spironolactone is effective

71
Q

Why is spironolactone abetter option for CHF than thiazide or loop diuretics?

A

You risk hypokalemia with these, but do not have that with spironolactone.

72
Q

What diuretics are indicated in right heart failure (chronic)?

A

Oral loop diuretics

73
Q

What diuretics are indicated in left heart failure (acute)?

A

This is a life-threatening situation and IV loop diuretics are indicated

74
Q

Which ADH inhibitor has signficant efficacy in acute heart failure symptoms?

A

Tolvaptan

75
Q

Why is Tolvaptan particularly useful for issues of hyponaturemia, in comparison to furosemide?

A

It is tremendously sodium sparing

76
Q

For pts with signficant hypertension who are prescribed multiple drugs, which diuretic will almost always be one of them?

A

Thiazide diuretic

77
Q

In what ay are thiazides useful for patients with calcium oxalate stones (kidney stones)?

A

Thiazide diuretics can decrease calcium concentrations in the urine by promiting calcium reabsorption in the distal convoluted tubule.

78
Q

Which diuretic can be used in cases of hypercalcemia? Which should be avoided?

A

Loop diuretics may be used with hydration to increase calcium excretion.

Thiazides ought to be avoided, as they increae clacium reabsorption

79
Q

What are some causes for Diuretic resistance?

A
  1. NSAID co-administration
  2. CHF
  3. Nephrotic syndrome
  4. Hepatic cirrhosis/ renal failure
  5. Therapeutic sta
80
Q

For what patients do you use combined Loop + Thiazide Diuretics? What issues can you run into with this combination?

A

Only in patients refractory to one or the other. May be to robust and lead to K+ wasting.

81
Q

What is the benefit of combined K+ sparing + loop or thiazide diuretics? (2)

A

Prevents hypokalemia

Allows you to avoid renal insufficiency