Diuretics Flashcards
MOA
Work to OPTIMIZE fluid volume in the body ==> optimize PRELOAD to reduce AFTERLOAD
What are the 4 common classifications of diuretics?
Thiazides diuretics
Loop diuretics
Potassium-sparing diuretics
Aldosterone antagonist diuretics
Which classification of diuretics is the most commonly prescribed?
Thiazide diuretics
What are the names of some common thiazide diuretics?
Chlorothalidone (Thalitone)
Hydrochlorothiazide (Microzide)
Metolazone (Zaroxolyn)
What are the names of some common loop diuretics?
Furosemide (Lasix)
Torsemide (Demadex)
Bumetanide (Bumex)
What are the names of some common K+-sparing diuretics?
Triamterene (Dyrenium)
Amiloride (Midamor)
What are the names of some common aldosterone antagonist diuretics?
Spironolactone (Aldactone)
Eplerenone (Inspra)
MOA - location
Kidneys
BP (decr.) = CO (decr.) x systemic vascular resistance (SVR)
Monitor BP response to different positions
Incr. dose ==> orthostatic HTN; dizziness
MOA - thiazides
Inhibit the NaCl transporter in distal renal tubule
Increase Na+ and H2O excretion
MOA - loops
Inhibit Na+/K+/Cl transporter in thick ascending limb
Increase Na+ and H2O excretion
K+ critical for muscle contraction –> increasing or decreasing can cause rhythm problems
MOA - K+-sparing
Inhibit Na channel-collecting tubule and collecting duct
Increase Na+ and H2O excretion (conserving K+ and H+)
MOA - aldosterone antagonists
Compete with aldosterone receptor sites in distal tubule
Increase Na+ and H2O excretion excretion (conserving H+ and K+)
What are some common adverse reactions of thiazide diuretics (Chlorthalidone; hydrochlorothiazide; metolazone)?
Electrolyte abnormalities (5H's - rhythm problems and muscle cramping): HYPOkalemia HYPOmagnesemia HYPERcalcemia HYPERglycemia HYPERericemia
Increased urination
Which class of diuretics is he most potent (Pt. loses a lot of K+)?
Loop diuretics
What are some common adverse reactions of loop diuretics (furosemide, torsemide, bumetanide)?
Electrolyte abnormalities: HYPOkalemia HYPOmagnesemia HYPOcalcemia (+/-) HYPERuricemia
Greater electrolyte depletion, esp. K+
What are indicators of HYPOkalemia?
Weakness Fatigue Muscle cramps Constipation Dysrhythmia
What are indicators of HYPOmagnesemia?
Weakness Confusion Diminished reflexes (LMN) Muscle twitching Dysrhythmia
What are indicators of HYPERcalcemia?
N/V Excessive thirst Frequent urination Constipation (Others as mentioned: weakness, fatigue, muscle cramps, constipation, dysrhythmia, confusion, diminished reflexes, muscle twitching)
Which class(es) of diuretics are commonly combined with other diuretics?
Potassium-sparing:
Enhances diuresis of other diuretics
Offsets HYPOkalemia caused by chronic therapy with thiazides or loops
Aldosterone antagonists:
Enhances diuresis of other diuretics
Offsets HYPOkalemia caused by chronic therapy with thiazides or loops
What are common adverse reactions of K+-sparing diuretics?
HYPERkalemia
Kidney stones
Increased urination
Which class of diuretics is indicated for HTN and HF?
Aldosterone antagonists
What are common adverse reactions of aldosterone antagonist diuretics?
HYPERkalemia
Gynecomastia
Impotence
Which class(es) of diuretics can cause HYPERkalemia?
K+-sparing and aldosterone antagonists
Which class of diuretics can cause HYPOcalcemia?
Loops
