Module 13 - Part 2 Flashcards
______ are the mainstay of therapy for HTN.
diuretics
What are the three main classes of diuretics?
Loop diuretics
Thiazide diuretics
potassium sparing diuretics/aldosterone antagonists
Diuretics work by blocking ______ and ________ ion reabsorption from the nephron of the kidney.
sodium
chloride
By preventing the reabsorption of Na+ and Cl-, diuretics make an osmotic pressure within the tubule that prevents the _____ of _______.
reabsorption of water
Diuretics produce more _______ decreases in BP at sites of ____ sodium reabsorption.
effective
high
______ diuretics produce the largest decrease in BP since 20% of sodium is reabsorbed at its site of action.
Loop diuretics (the most effective diuretics available
Mechanism of action of loop diuretics?
They act by blocking sodium and chloride ion reabsorption in the thick ascending limb of the LoH
Loop diuretics are usually reserved for situations that required rapid loss of fluid such as? (3)
Edema
Severe HTN that does not respond to milder diuretics
Severe renal failure
What are the adverse effects of Loop diuretics?
Hypokalemia
Hyponatremia
Dehydration
Hypotension
Low potassium levels in the blood, may also cause fatal ______ ________.
Hypokalemia
may cause fatal cardiac dysrhythmias
Why does hypokalemia occur as an adverse effect when taking loop diuretics if they decrease sodium reabsorption?
The transporter responsible for reabsorbing Na+ and Cl- also transports K+ into the blood, which is why hypokalemia occurs
Most commonly used class of drugs to treat HTN
Thiazide diuretics
Thiazide diuretics act by two main mechanisms, what are these?
Blocking sodium chloride ion reabsoprtion in the distal tubule
Decreasing vascular resistance (unknown mechanism)
For many hypertensive patients, thiazide diuretics alone _____ enough to control BP.
are
Adverse effects of thiazide diuretics?
Hypokalemia - may cause fatal cardiac dysrhythmias
Dehydration
Hyponatremia
Potassium sparring diuretics are also called this.
Aldosterone antagonists
Aldosterone Antagonists/Potassium sparing diuretics mechanism of action?
Act by inhibiting aldosterone receptors in the collecting duct
Blocking these receptors causes increased sodium excretion and potassium retention
What is the main use of potassium sparing diuretics?
Main use is in combination with thiazide and loop diuretics to counteract hypokalemia side effect
Potassium sparring diuretics should not be used with these.
Ace inhibitors or renin in inhibitors
What is the primary side effect of potassium sparring diuretics?
Hyperkalemia - may result in fatal dysrhythmias
Beta blockers are effective at treating HTN and they do this through two distinct mechanisms, what are these?
Blocking cardiac beta 1 receptors
Blocking beta 1 receptors on juxtaglomerular cells
What does blocking beta 1 receptors do?
Blocks catecholamine (e.g. epinephrine) binding to beta 1 receptors, decreasing CO and thus BP
What does blocking beta 1 receptors on juxtaglomerular cells do?
Beta blockers decrease renin release and therefore decrease RAAS mediated vasoconstriction
Beta blockers all have this suffix.
“olol”