Diuretics Flashcards
How do thiazide diuretics work?
On distal convoluted tubule
Na/Cl transporter
10% Sodium reabsorption
Possible vasodilation effect
What thiazide diuretic is available in an injectable form?
Chlorothiazide
If a patient has allergy to sulfonamides they are likely allergic to….
allergic to many things in general
What is the initial effect of thiazide diuretics?
plasma volume depletion= decreased BP
Can you increase the dose of diuretics to increase effect?
No
What electrolyte effects may happen when taking a thiazide diuretic?
Increased loss of Na and Cl
Loss of K (Hyponatremia)
Loss of Mg
Increased Ca (Hypercalcemia)
What are some ADRs of thiazide diuretics?
Hyponatremia Hyperuricemia Volume depletion Hypercalcemia Hypersensitivity Hyperglycemia Hyperlipidemia Hypokalemia
Dose a thiazide diuretic
Hydrochlorothiazide 25 mg
1 table daily
Dose a thiazide like diuretic
Chlorthalidone 50mg
1 tablet daily
When is addition of a thiazide to a loop diuretic helpful?
Refractory edema in heart failure
Cirrhosis
Nephrotic syndrome
Renal failure
What is the MOA of loop diuretics?
Work on ascending Loop of Henle on Na/K/Cl transporters
25-30% sodium reabsorption
Can you increase the dose of loop diuretics to get an increased effect?
Yes
What electrolyte effects can loop diuretics cause
Increased excretion Na and Cl Loss of K Loss of Mg Loss of Ca -reduced renal vascular resistance
What is the onset of loop diuretics?
Relatively rapid
Symptom relief in hours to days
What are the main uses in the U.S. of loop diuretics?
Heart Failure
Nephrotic Syndrome
Renal insufficiency
Cirrhosis
Dose a loop diuretic
Furosemide 40mg
1 tablet daily
How do aldosterone antagonist potassium-sparing diuretics work?
Block stimulation of Na/K exchange in collecting tubule
Spironolactone has hormonal effect
How does Amiloride work?
sodium channel blocker in the collecting tubule
What are the indications for Spironolactone?
Management of CHF
Cirrhosis of liver w/edema and/or ascites
Nephrotic syndrome
What are the indications for Amiloride
Adjunctive treatment with thiazide or other kaliuretic-diuretics in CHF or HTN to restore normal serum K levels
-or to prevent development of K in those at risk
What are the ADRs of Spironolactone?
Gastric upset
Gynecomastia
Menstrual irregularities
What are the ADRs of Amiloride/Triamtrene?
Leg cramps
Increased BUN
Potassium retention
Increased uric acid
What are potential problems when using a potassium-sparing diuretic with a thiazide diuretic?
Excess diuresis
Blunt hypokalemia
Dose a potassium-sparing diuretic that is approved for HTN
Amiloride 10mg
1 tablet daily
Dose a potassium-sparing diuretic that is approved for cirrhosis of the liver or Nephrotic syndrome
Sprionolactone 25 mg
1 tablet twice a day
How does Mannitol work?
Inhibits sodium reabsorption in the proximal convoluted tubule and Loop of Henle
When is Mannitol used?
Inpatient setting:
- Reduction of intracranial pressure
- Reduction of ocular pressure
What would you give to a patient with low potassium?
Potassium Chloride
K-Dur, Slow-K
What diuretics have been shown to be safe in children?
Thiazides and Spironolactone
