Diuretics

Question 1

Common Facts

Answer 1

Commonly used to treat: hypertension
Common Adverse Reactions: increased urination, photosensitivity
(thiazide and loop diuretics)
Common Auxiliary Label(s): avoid prolonged exposure to sun
(thiazide and loop diuretics)
May be advisable to eat bananas or drink
orange juice (thiazide and loop diuretics)

Question 2

Mechanism of Action

Answer 2

Increase elimination of water and electrolytes

Decreases blood volume, peripheral resistance, cardiac output, and therefore, blood pressure

Question 3

Thiazide Diuretics

Answer 3

Decrease vasoconstriction, peripheral resistance, blood pressure
Act in distal convoluted tubule
Weak acids; highly protein bound
Additional adverse reactions: dehydration, electrolyte deficiencies,
excess uric acid and gout flare-ups

Question 4

Notes

Answer 4

Take in morning to avoid nocturia
Effect reduced when taken concurrently with NSAIDs
Inhibit 5-10% sodium reabsorption

Question 5

Hydrodiuril

Answer 5

Generic name: hydrochlorothiazide (HCTZ)
Tablets: 25mg, 50mg
Common Doses: 12.5-50mg once daily (QAM)

Question 6

Lozide

Answer 6

Generic name: indapamide
Tablets: 1.25mg, 2.5mg
Commonly dosed once daily (QAM)

Question 7

Zaroxolyn

Answer 7

Generic name: metolazone
Tablets: 2.5mg
Commonly dosed once daily, or a few days each week (mornings)

Question 8

Loop Diuretics

Answer 8

Act in ascending loop of Henle
Up to 98% protein bound
Additional adverse reactions: hypokalemia, dehydration, severe
hypotension
Notes: take in morning to avoid nocturia

Question 8

Loop Diuretics

Answer 8

Act in ascending loop of Henle
Up to 98% protein bound
Additional adverse reactions: hypokalemia, dehydration, severe
hypotension
Notes: take in morning to avoid nocturia
Effect reduced when taken concurrently with NSAIDs
Inhibit 20-30% sodium reabsorption= most potent diuretics
Often taken with potassium supplement

Question 9

Lasix

Answer 9

Generic name: furosemide
Tablets: 20mg, 40mg
Commonly dosed 1-2 times daily

Question 10

Potassium Sparing Diuretics/Aldosterone Receptor Antagonists

Answer 10

Inhibit sodium reabsorption while sparing potassium loss
Aldactone=competitive antagonist of aldosterone
Adverse reactions: hyperkalemia (increased risk when taken with ACEIs)
-Gynecomastia
-Hirsutism
Notes: effectiveness increased when combined with thiazide
-inhibit 1-3% sodium reabsorption; less effective than thiazide and loop diuretics

Question 11

Aldactone

Answer 11

Generic name: spironolactone
Tablets: 25mg, 100mg
Common doses: 25-100mg once daily
Auxiliary labels: take with food
                           -Avoid salt substitutes and potassium rich diets

Question 12

Cardioglycosides

Answer 12

Commonly used to treat: heart failure
Mechanism of Action: increase cardiac output and force of myocardial contractions
Notes: narrow therapeutic index (lethal dose close to therapeutic dose)
-Digitalis toxicity: arrhythmias, dizziness, convulsions, delusions, coma
Common adverse reactions: photophobia, visual disturbances, weakness, gynecomastia

Question 13

Toloxin

Answer 13

Generic name: digoxin
Tablets: 0.0625mg, 0.125mg, 0.25mg
Commonly dosed once daily