Understanding Diuretics and Their Uses

Jan 15, 2025

Diuretics

Overview

  • Diuretics help remove excess fluid from the body by stimulating urine production.
  • Types: Loop, Thiazide, Potassium-sparing, Osmotic.
  • Memory trick: "Diuretics think dry inside."

Uses of Diuretics

  • Heart Failure: Treat fluid retention and edema due to heart's weakened state.
  • Hypertension: Less fluid means less pressure on vessels.
  • Chronic Kidney Disease (CKD): Help reduce fluid retention and manage potassium levels.

Types of Diuretics

Loop Diuretics

  • Suffix: End in "-mide" or "-nide" (e.g., Furosemide, Bumetonide, Torsomide).
  • Mechanism: Inhibit reabsorption of sodium and chloride in the kidneys.
    • Works on distal/proximal tubules and Loop of Henle.
  • Potassium Wasting: Major side effect is hypokalemia (low potassium).
    • Normal potassium level: 3.5-5.0 mEq/L.
  • Nursing Considerations:
    • Monitor potassium levels.
    • Administer potassium replacement orally or intravenously (must not crush/chew extended-release tablets).
    • Administer Furosemide slowly to avoid ototoxicity.

Thiazide Diuretics

  • Suffix: End in "-thiazide" (e.g., Hydrochlorothiazide, Chlorothiazide).
  • Mechanism: Similar to Loop Diuretics but less potent, act on ascending loop of Henle and early distal tubule.
    • Also potassium wasting.
  • Nursing Considerations:
    • Monitor potassium levels.
    • Avoid in patients with gout or sulfur allergies.

Potassium-Sparing Diuretics

  • Common Drug: Spironolactone (Aldactone).
  • Mechanism: Blocks aldosterone, leading to sodium and water excretion but sparing potassium.
  • Nursing Considerations:
    • Monitor for hyperkalemia (high potassium).
    • Advise patients to avoid high-potassium foods and potassium supplements.

Osmotic Diuretics

  • Common Drug: Mannitol (Osmitrol).
  • Use: Treat cerebral edema and decrease intraocular pressure.
  • Mechanism: Increases filtrate thickness, preventing water reabsorption.
  • Nursing Considerations:
    • Administered IV; check for crystallization.
    • Monitor neuro assessments for cerebral edema.

General Nursing Considerations for Diuretics

  • Administer diuretics in the morning to avoid nocturia (night peeing).
  • Educate on orthostatic hypotension and low sodium diet.
  • Monitor daily weights, intake/output, and potassium levels.
  • Report acute weight gain (2-3 lbs).

Potassium Wasting vs. Sparing Diuretics

  • Wasting: Loop and Thiazide Diuretics.
  • Sparing: Spironolactone (Aldactone).

Practice Question

  • Spironolactone and high potassium levels: Report potassium levels before administering if above normal range (e.g., 5.3 mEq/L).

For additional resources and practice questions, refer to the NCLEX study materials mentioned in the lecture.