Pharm 20 - Diuretics Flashcards Preview

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Flashcards in Pharm 20 - Diuretics Deck (56)
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Aliskiren MOA

Renin inhibitor (decreases conversion of angiotensinogen to angiotensin I -> reduces substrate for ACE -> decreases arteriolar vasoconstriction, aldosterone synthesis, renal proximal tubule NaCl reabsorption and ADH release)


Aliskiren clinical applications

HTN (can be used even in pts w/ renal insufficiency)


Aliskiren adverse effects

Hypotension, acute renal failure, angioedema; also rash, diarrhea, cough


Aliskiren contraindications

Pregnancy, hyperkalemia, Hx of angioedema, cyclosporine Tx


Aliskiren therapeutic considerations

Plasma concentration and half-life increased by atorvastatin and ketokonazole, decreased by furosemide; may reduce proteinuria in chronic kidney disease.



ACE inhibitors
1) decrease conversion of ATI to ATII -> decreases arteriolar vasoconstriction, aldosterone synthesis, renal proximal tubule NaCl reabsorption and ADH release (same as Aliskiren)
2) Inhibit degradation of bradykinin -> increase vasodilation (unique to ACE inhibitors)


[-PRIL] clinical applications

HTN, heart failure, diabetic nephropathy, MI


[-PRIL] adverse effects

Angioedema (more frequrent in black pts), agranulocytosis, neutropenia; also dry cough, edema, hypotension, rash, gynocomastia, hyperkalemia, and proteinuria


[-PRIL] contraindications

Pregnancy, B/L renal artery stenosis, renal failure, Hx of angioedema


[-PRIL] therapeutic considerations

Dry, non-productive cough and angioedema are due to bradykinin action; 1st dose hypotension and/or renal failure more common in pts w/ B/L renal artery stenosis; hyperkalemia more common if used w/ potassium-sparing diuretics; delay progression of cardiac contractile dysfunction after MI; delay progression of diabetic nephropathy



Angiotensin II Receptor Antagonists (AKA "ARBs"); antagonize action of angiotensin II at AT receptor, may also indirectly increase vasorelaxant AT2 receptor activity


[-SARTAN] clinical applications

HTN, heart failure, diabetic nephropathy, MI (same as ACE inhibitors) AND prevention of stroke (reduced platelet aggregation, decreased serum uric acid, decreased atrial fibrillation, anti-diabetic effects)


[-SARTAN] adverse effects

Thrombocytopenia, rhabdomyolysis, angioedema; also hypotension, diarrhea, asthenia, dizziness


[-SARTAN] contraindications

Pregnancy, B/L renal artery stenosis


[-SARTAN] therapeutic considerations

Can be used w/ ACE inhibitors to increase survival in heart failure; less cough/angioedema than ACE inhibitors...but less effective vasodilation too


Nesiritide MOA

B-Type Naturetic Peptide (BNP); increases intracellular concentrations of cGMP by binding to guanylyl cyclase receptor NPR-A of vascular smooth muscle and endothelial cells -> smooth muscle relaxation


Nesiritide clinical applications

Acutely decompensated heart failure


Nesiritide adverse effects

Hypotension, arrhythmia, renal dysfunction; also headache, confusion, somnolence, tremor, pruritis, nausea


Nesiritide contraindications

Cardiogenic Shock, Systolic BP < 90


Nesiritide therapeutic considerations

Decreases pulmonary capillary wedge pressure and systemic vascular resistance; Improves stroke volume; Associated with fewer instances of arrhythmia than dobutamine; Risk of hypotension increased when co-asministered with ACE inhibitors; lower plasma aldosterone and endothelian-1; drug is a peptide, so it can't be given orally



Vasopressin Receptor 2 (V2) Antagonist, prevents vasopressin-stimmulated water reabsorption via V2-coupled aquaporin channels in apical membrane of collecting duct


[-VAPTAN] clinical applications

Euvolemic hyponatremia, SIADH, Heart failure, Ascites due to cirrhosis, ADPKD


[-VAPTAN] adverse effects

Atrial fibrillation; also orthostatic hypotension, HTN, hypokalemia, thirst, dyspepsia, headache, polyuria


[-VAPTAN] contraindication

Concurrent use of CYP3A4 inhibitors (grapefruit juice); hypovolemic hyponatremia


[-VAPTAN] therapeutic considerations

Conivaptan is non-selective for V1/V2 and must be administered IV; Tolvaptan is oral and V2-selective - may be able to retard ADH-driven renal cyst growth in ADPKD


Acetazolamide MOA

Carbonic Anhydrase inhibitor: noncompetitively/reversibly inhibits proximal tubule cytoplasmic carbonic anhydrase II and luminal carbonic anhydrase IV -> inhibits sodium and bicarbonate reabsorption -> more sodium bicarbonate in distal segments of nephron


Acetazolamide clinical applications

High-altitude sickness (prophylaxis), heart failure, epilepsy, glaucoma, hyperuricemia/gout (alkalizes urine and increase excretion of organic anions (uric acid, ASA, etc))


Acetazolamide adverse effects

Metabolic acidosis (mild/moderate with normal clinical use), sulfonamide adverse rxns (anaphylaxis, blood dyscrasia, erythema multiforme, fulminante hepatic necrosis, Stevens-Johnson syndrome, toxic epidermal necrolysis); also N/V, D, wt gain, loss of appetite, tinnitus, parethesia, somnolence, polyuria


Acetazolamide contraindication

In the ciliary process of the eye, carbonic anhydrase inhibition reduces secretion of aqueous humor (reduces intraocular pressure); use of ASA increases plasma concentration -> can cause CNS toxicity


Mannitol MOA

Osmotic diuretic, filtered at glomerulus but not reabsorbed; effect is greatest in proximal tubule (osmotic diuresis can also occur the same way when you use radio contrast dyes or in hyperglycemia)