Quiz 3 Study Guide: Antihypertensives Flashcards
What does a Diuretic do?
Depletes sodium
Reduces blood volume
Where do diuretics work?
In the Renal Tubule
What are examples of Diuretics?
Thiazides (hydrochlorthiazide)
Loop (furosemide)
Aldosterone (spironolactone and amiloride)
Osmotic (mannitol)
Carbonic anhydrase inhibitor (acetazolamine)
What are the drug categories of antihypertensives?
Diuretics Alter sympathetic tone Arteriole Dilators Calcium Channel Blockers Angiotensin affectors Ganglionic Blockers
Characteristics of Thiazide Diuretics (hydrochlorthiazide, chlorthalinidone)…
-First order drug
Causes:
- Electrolyte imbalances especially K+ (hypokalemia)
- Glucose intolerant
- inhibited by NSAIDS
Where do Thiazide Diuretics work?
Distal Convoluted Tubule
What are characteristics of Loop Diuretics (Furosemide, Bumetanide)
- Very Efficacious
- Reduce NaCl reabsorption at expense of K+ and H+ ions which are lost in the urine.
Where do loop diuretics work?
Thick Ascending Limb
Where do aldosterone (Potassium Sparing) diuretics work?
Collecting Tubule
What are characteristics of aldosterone (potassium sparing diuretics such as spironolactone and amiloride?
-Prevent K+ secretion by antagonizing effects of aldosterone in collecting tubules (spironolactone)
or
- prevent Na+ influx through icon channels in the luminal membrane (amiloride)
- can be used with loop diuretics to offset hypokalemia
- not used with ACE -1
What is an example of an osmotic Diuretic?
mannitol
Where do osmotic Diuretics work and how?
Thin Descending Limb
- Mannitol stays in the urine (not reabsorbed) and so it absorbs more fluid into the urine.
What is Mannitol (Osmotic Diuretic) used for?
Increased intracranial pressure after head trauma.
*NOT hypertension
What is an example of a Carbonic Anhydrase Inhibitor?
Acetazolamide (Diamox)
Where do Carbonic Anhydrase Inhibitors (Acetazolanide) work and how?
Proximal Convoluted Tubule
-Shuts down reabsorption of H2CO3 into interstitial space = less Na+ reabsorption and more Na+ in lumen.
