What are the 3 Classifications of Diuretics?

1.  High Ceiling Loop Diureteics

2. Thiazides & Related Diuretics

3.  Potassium Sparing Diuretics

How do most diuretics work?

Most block absorption of Na & Cl and therefore,

prevent passive reabsorption of water.

Which diuretic produces most diuresis and why?

High Celing Loops (Lasix) because it is located early in the nephron and is in a position to block the

greatest amount of solute reabsorption.

Where does Lasix work?

In the Loop of Henle

What is one of the primary differences between Loop Diuretics and Thiazides?

Loop's work even if glomerular filtration rate is low.

What is the one unique side effect of High-Ceiling Diuretics?

Reversible hearing loss.

What is the MOA for Lasix

Blocks Na & Cl in the ascending loop of henle.

What are the pharmacokinetics of Lasix?

Po, IV, IM

IV when needing rapid diuresis

hepatic / Renal Metabolism

Therapeutic Uses of Lasix?

    - rapid and massive diuresis

-Pulmonary Edema

-Edema of organs

-HTN can't be controlled with other diuretics

-renal impariement because works even with low glomerular filtration rate

Adverse Effects of High-Ceiling Diuretics?

HypoNa, HypoCl, Dehydration, Hypotension, HypoK, Ototoxicity,

Important Drug Interactions with High-Ceiling Diuretics

Digoxin - toxicity - V-arrhythmia

Lithium - toxicity - Low Na

NSAIDS - can attenuate diuretic effect

What is the MOA for Thiazides and Related Diuretics

Hydrochlorathiazide (Hydrodiurl)

MOA - blocks NAa & Cl reabsorption in the distal convoluted tubule BUT requires adequate

kidney function and GFR.

What are the pharmacokinetics of

Thiazide and Related Diuretics?

Oral only.

Mostly excreted unchanged in the urine

What are the therapeutic uses of Thiazide?

Essential HTN

Edema

Adverse Effects of Thiazide?

HypoNa, HypoCl, Dehydration,l hyperglycemia, hyperuricemia

What are the major drug interactions with Thiazides?

Digoxin - toxicity

Lithium - toxicity

NSAIDS - blunt effects

Name 3 K+ Sparing Diuretics

Spironolactone

Triamterene

Amiloride

What is the MOA for K+ Sparing Diuretics?

Spironolactone

BLocks the action of aldactone in the distal nephron;

retention of K and exretion of Na.

diuresis is scanty because at tend of nephron

What are the therapeutic uses of Aldactone (spironolactone)

HTN

Edema

HF

Principle adverse effect of K+ sparing diuretics?

HyperK+

What are the major drug interactions with K+ Sparing Diuretics?

NEVER combine with K+ Supplements

Cautiously with ACE's, ARB's - raise K_ levels too

What is the primary use of K+ sparing diuretics?

To counteract loss of K+ from other diuretics.

Which diuretics are used to treat HTN and edema associated with heart failure, cirrhosis, and kidney disease?

High-Celing and Thiazides

What are the 5 key parts of the nephron?

Glomerulus

Promimal Convoluted Tubule

Loop of Henle

Distal Convoluted Tubule

Collecting Duct

What are the 3 basic functions of the kidney?

1.Cleansing of extracellular fluid and maintenance of ECT volume and composition

2. Maintenance of acid-base balance

3. Excretion of metabolic wastes and foreign substances

What diuretic still works even with renal impairment?

Loop Diuretics - Lasix

Name some thiazide duretics

thiazine, hctz, diuril, esidrix, chlorthalidone

What are the 2 K+ wasting diuretic groups?

High Ceiling Loops

Thiazides

What are the two groups of K+ sparing diuretics?

Aldosterone Antagonists - aldactone

NonAldoserone Antagonists - triamterene, eplerone

What painful condition is associated with a SE of diuretics?

gout secondary to hyperuricemia!

If a pt is allergic to Sulfa, which diuretic group can you NOT use?

High Ceiling Loops

If having to supplement with K+, what is the average dose?

40-80 meq/day with food or full glass of water.

Which diuretics do you have to keep in a dark container?

Aldactone

What is a common blood dyscrasia that you should monitor for with diuretics?

Agranulocytosis

What are the possible SE's of mannitol?

1.  Inc blood volume-->CHF, PE

2.  Rebound ICP

How do diuretics work primarily?

Interfering with reabsorption

Where does 65% of filtered NaCl reabsorb?

PCT

Where in the kidney do you get the most diuretic effect?

Early in the neprhon

What is the most commonly used diuretic?

HCTZ

What are the two effects of K+ sparing diuretics?

1.  modest diuresis

2.  substantial decrease in K+ excretion

What is the ONLY aldosterone antagonist?

Aldactone

How does aldactone work?

blocks actions of aldosterone in distal nephron

How quickly does aldactone work and what does it work best to treat?

delayed effect - up to 48 hrs

HTN, edema, HF

What is a unique SE of Aldactone?

Steroid derivative - endocrine effects

What should you NEVER combine with K+ sparing diuretics?

K+

Caution with ACE, ARB, DRI because they increase K+ levels too

What classification does Triamterene fall into and what is it's MOA?

1.  Nonaldosterone antagonis

2.  Disrupts Na K exchange in distal nephron resulitng in decreased Na reabsorption and Decreased K+ secretion