Diurectics Flashcards
What do you need for heparin to work?
Antithrombin
What do diuretics block?
These drugs block sodium & chloride reabsorption at different sites in the nephron
What do diuretics increase?
Increases urinary sodium and water loss
What are diuretics used to treat? (6)
Used in treatment of HTN, heart failure, edematous states, hypercalcemia, renal dysfunction, & glaucoma
Review diuretics action at the nephron.

Where do Carbonic Anhydrase Inhibitors bind?
drugs bind to carbonic anhydrase in the proximal renal tubule
What do Carbonic Anhydrase Inhibitors result in?
results in decreased reabsorption of sodium, bicarbonate, & water (water & bicarbonate ion loss)
What is the functional unit of the kidney?
Nephron
What drugs are Carbonic Anhydrase Inhibitors?
acetazolamide
What are the clinical uses for Carbonic Anhydrase Inhibitors?
acetazolamide
- decrease intraocular pressure in tx of glaucoma (decreases formation of aqueous humor
- tx of idiopathic intracranial HTN (inhibits formation of CSF)
- altitude sickness
What is the amount of sodium reabsorbed?
- 2/3 at the proximal convoluted tubule
What are side effects of Carbonic Anhydrase Inhibitors?
Acetazolamide
- metabolic acidosis (loss of bicarbonate ions)
What is the action of Loop Diuretics?
Acts by impairing the activity of the Na-K-2Cl transport protein in the ascending loop of Henle
How much of sodium is ascending reabsorbed at the loop of henle?
where 20% - 30% of Na is normally reabsorbed
What are we inhibiting with Loop Diuretics?
Inhibit reabsorption of sodium, potassium, & chloride
Loop diuretics are the most _____ diuretics
potent
What are the drugs of loop diuretics?
furosemide, torsemide, bumetanide, ethacrynic acid, azosemide
What is the formularies for Furosemide?
Oral or IV
What is the onset of Furosemide?
Fast onset of action; produces diuresis within 5-10 minutes
When is the peak effect of Furosemide?
peak effect 30 minutes
What is the duration of Furosemide?
duration of action 2 – 6 hours
What is the dose Furosemide in normal renal function?
With normal renal function, 40mg IV will produce maximal diuresis
What is the dose Furosemide in renal dysfunction?
With chronic renal insufficiency, 160mg – 200mg slow IV produces maximal diuresis, continuous infusion can also be considered instead of repeat bolus doses
What is the formularies of Bumetanide?
Can be given oral, IM, or IV
What is the potency of Bumetanide?
40 times more potent than furosemide
What is the clinical use of Loop Diuretics?
first-line therapy in patients w/fluid retention from heart failure; HTN; pulmonary edema; intracranial pressure
What is the most common side effect of Loop Diuretics?
hypokalemia
What are other side effects of Loop Diuretics?
- Hypovolemia
- Increase tissue concentrations of aminoglycosides enhancing nephrotoxicity
- Potentiate nondepolarizing NMBDs
Patients allergic to ______ may exhibit cross-sensitivity to furosemide
sulfonamide drugs
Plasma concentrations of ____ may be acutely increased w/IV furosemide
lithium
Define components of hypokalemia and loop diuretics.
increases likelihood of digoxin toxicity
Define components of hypovolemia and loop diuretics.
- should only be administered to patients w/normal or increased intravascular fluid volume
- resulting hypotension can exacerbate renal ischemic injury
What do Thiazide Diuretics produce?
These drugs produce diuresis & Na loss by inhibiting reabsorption of Na & chloride ions in distal convoluted tubule; block Na-chloride cotransporter/water
What is urinary excretion of Thiazide Diuretics?
Urinary excretion of Na, chloride, & K ions; also stimulate reabsorption of Ca in distal convoluted tubule
What are drugs of Thiazide Diuretics?
HCTZ, chlorthalidone, metolazone
What is the first line use of Thiazide Diuretics?
- First-line therapy for essential HTN by decreasing extracellular fluid volume & peripheral vasodilation
- tx of calcium-containing renal calculi (stimulate Ca reabsorption)
What is the components of Chlorthalidone?
longer acting, reduces risk of major cardiovascular events
What are side effects of Thiazide Diuretics?
- Hypokalemia, hypochloremia, metabolic alkalosis
- cardiac arrhythmias d/t hypokalemia or hypomagnesemia, hypercalcemia (esp in pts receiving Ca or Vit. D supp)
hypokalemia may predispose pts to ______
dig toxicity
What are side effects of Thiazide Diuretics?
- Potentiation of nondepolarizing NMBDs
- Potentiate lithium toxicity (promote lithium reabsorption)
- Hyperglycemia in diabetic pts
- Hyperlipidemia
Must consider _________ status in patients receiving thiazide diuretics & scheduled for surgery
fluid volume
Patients w/ ________ may demonstrate cross-reactivity to thiazide & loop diuretics
Patients w/sulfa allergy may demonstrate cross-reactivity to thiazide & loop diuretics
What is the relationship of thiazide diuretics and diabetic patients?
Hyperglycemia in diabetic pts (esp when used in combo w/beta blockers)
What do Osmotic Diuretics result in?
- Osmotic diuretics result in increased plasma & renal tubular fluid osmolality which results in osmotic diuresis
Where do Osmotic Diuretics act?
Act primarily at proximal renal tubules & loop of Henle
What is the osmotic drugs in clinical use?
mannitol
What is the cellular effects of Osmotic Diuretic: Mannitol?
Increases plasma osmolarity & draws fluid from intracellular to extracellular spaces
What does Osmotic Diuretic: Mannitol expand?
Acute expansion of intravascular fluid volume
What pt population is Osmotic Diuretic: Mannitol poorly tolerated?
may be poorly tolerated in patients w/borderline cardiac function
What are the clinical uses of Osmotic Diuretic: Mannitol?
- Acute management of elevated ICP
- tx of glaucoma
- used during cardiac & major vascular surgery for renal protection
What are the renal protection effects of mannitol?
- Renal protection effects:
- osmotic diuresis that forces casts & necrotic debris out of renal tubules
- vasodilation of renal vasculature by release of prostaglandins which improves renal blood flow/protect kidneys from acute failure following renal tubular necrosis
- oxygen-free radical scavenger property may prevent cellular injury
What are side effects of Osmotic Diuretic: Mannitol?
- May cause hypernatremia from water diuresis
- May cause pulmonary edema
- May cause hypovolemia, hypokalemia, plasma hyperosmolarity
increased intravascular volume with Osmotic Diuretic: Mannitol in pts w/__________
poor LV function
- increase risk of pulmonary edema
Where do Potassium-Sparing Diuretics act?
Act on the renal collecting ducts
NSAIDs block what?
Prostaglandins and this can be bad for the kidneys
What are the two groups off Potassium-Sparing Diuretics?
pteridine analogues & aldosterone receptor blockers
What are the effects of pteridine anaglogues Potassium-Sparing Diuretics?
prevent Na reabsorption
What are pteridine anaglogues Potassium-Sparing Diuretics drugs?
triamterene & amiloride
What is the MOA of Aldosterone antagonists Potassium-Sparing Diuretics?
prevent synthesis & activation of aldosterone-dependent Na-K-ATPase pump which decrease Na reabsorption without increased K excretion
What are the drugs of Aldosterone antagonists Potassium-Sparing Diuretics?
- spironolactone
- eplerenone
- used w/thiazide diuretic
What are the clinical uses of Potassium-Sparing Diuretics??
- tx of essential HTN (in combo w/thiazides) – prevents thiazide-induced hypokalemia & hypomagnesemia
- promotes diuresis in patients w/edema & fluid overload asso/w hyperaldosteronism such as liver cirrhosis, nephrotic syndrome, & heart failure
What is the effect of spironolactone with ACE-I?
spironolactone w/ ACE-I in tx of heart failure decreases CV morbidity & mortality
What are the side effects of Potassium-Sparing Diuretics?
hyperkalemia (especially when combined w/ACE-Is or ARBs or w/NSAIDS)
What do Dopamine Receptor Agonists result in?
These drugs result in natriuresis & increased renal blood flow via action on renal tubular dopamine-1 (D1) receptors
Where is the activation of Dopamine Receptor Agonists? What does it cause?
Activation of D1 receptors in proximal renal tubule & loop of Henle increases cyclic AMP production resulting in inhibition of the Na-H exchange & Na-K-ATPase pump
What do D1 receptors also mediate?
increased renal blood flow & increased GFR
What is an example of D receptor agonists?
fenoldopam
- fast-acting IV antihypertensive used in short-term treatment of severe HTN
- administration results in increased renal blood flow & decreased SVR
What is the metabolism divisions of lipoprootein?
exogenous & endogenous pathways
What are the exogenous pathway of Lipidoprotein metabolism?
Exogenous pathway: processing of dietary fats, cholesterol, & lipid-soluble vitamins
What are the endogenous pathway of Lipidoprotein metabolism?
hepatic cholesterol synthesis & its distribution to peripheral tissues
What lipoproteins increased risk of cardiovascular disease?
Increased plasma concentration of total & LDL cholesterol
What lipoproteins reduce the risk of atherosclerosis & CV events?
Higher HDL cholesterol levels
What is the characteristics of lipoproteins and CAD?
Lowering plasma concentrations of total & LDL cholesterol w/ drugs decreases risk of cardiac events in patients with and without CAD
Lipid-lowering agents are used to treat ___________
hyperlipidemia
What is an example of Lipid-Lowering Agents?
Statins
What are statins MOA?
Statins are competitive inhibitors of HMG-CoA reductase, the enzyme that catalyzes cholesterol biosynthesis within the liver
What do Lipid-Lowering Agents: Statins cause?
- Cause decreased cholesterol synthesis and increased LDL uptake by liver resulting in decreased LDL concentration
- also cause increase in HDL
What is the metabolism of Lipid-Lowering Agents: statins?
Hepatic metabolism – CYP3A4
What drugs are Lipid-Lowering Agents: statins?
atorvastatin, fluvastatin, lovastatin, pravastatin, rosuvastatin, simvastatin
What do Lipid-Lowering Agents: Statins stabilize?
Stabilize atherosclerotic plaques
What is the properties of Lipid-Lowering Agents: Statins?
Antiinflammatory, antioxidant, & vasodilatory properties
What are the skeletal muscle effects of Statins?
- Statin-related myotoxicity (skeletal muscles)
- myalgia
- myositis
- CPK can range between mild and extreme elevations
- rhabdomyolysis
Severe statin muscle-related adverse events secondary to _______
drug interactions
What are the drug interactions that cause statin-Statin-related myotoxicity (skeletal muscles)?
Drug interactions with agents that are also metabolized by hepatic CYP450 system
What drugs are most frequently associated with Myopathy?
most frequent w/ atorvastatin, simvastatin, lovastatin
What are the CYP3A4 inhibitors that can effect statin levels?
CYP3A4 inhibitors (warfarin, protease inhibitors, macrolide antibiotics, azole antifungals) may increase concentration of statins & lead to myopathy
___________ does not increase incidence of statin-induced myopathy
Succinylcholine
What does hepatic dysgunctioon with statins manifest as?
manifests as plasma aminotransferase elevation
What are the two primary side effects of Statins?
- Statin-related myotoxicity (skeletal muscles)
- Hepatic dysfunction