4.3 - Antihypertensive Drugs Flashcards
What are the anti-hypertensive drugs?
A: Angiotensin Converting Enzyme (ACE) Inhibitors + AngII Receptor blockers
B: B blockers
C: Calcium channel blockers
D: Diuretics
E: Etcetera (vasodilators)
What are ACE inhibitors used to treat?
HTN + Chronic HF
–> reduce activity of RAS system by inhibiting the formation of AngII
What are the effects of decreased AngII?
Less vasoconstriction
Less aldosterone
–> Less K+ secretion
–> Less Na+ and water retention
ACE is necessary for metabolizing bradykinin, what does this mean for some patients?
Bradykinin builds up in blood
–> some patients get a dry cough and must stop taking medication
What are the physiological effects of ACE inhibitors?
Decreased AngII
–> Decreased Na+ / water retention
–> Decreased secretion of K+
–> Vasodilation
^ Decreased blood pressure (afterload)
–> Reduced vascular and cardiac remodeling
What are the Angiotensin converting enzyme inhibitors?
Ramipril, perindopril, enalapril, captopril
What are the adverse effects of ACE inhibitors
–> Hypotension
–> Dry cough, especially with captopril
–> Angioedema
–> Risk of hyperkalemia
What is angioedema?
Swelling of the face associated with use of ACE inhibitors
What are the AngII receptors blockers?
Losartan, irbesartan, valsartan
What are the osmotic diuretics?
Mannitol
What are the classes of natriuretics?
Carbonic Anhydrase inhibitors
–> acetazolamide
Loop Diuretics
Thiazides
K sparing
What transporter does a loop diuretic act on? Name a loop diuretic.
Furosemide
–> blocks Na/K/Cl transporter in ascending limb of loop of the nephron
What are the adverse effects of loop diuretics like furosemide?
–> Volume depletion
–> Hypotension
–> Hypo K, Mg, and Ca
–> Increase in uric acid and plasma lipids
–> Ototoxicity (esp when used in combination w aminoglycosides)
Which diuretic would you not prescribe to someone with gout?
Loop diuretic + thiazides
–> Adverse effects include increase in uric acid
Which diuretics would you not prescribe to someone with kidney stones?
Loop diuretics
–> Adverse effects include calcium secretion (so more will be passing through the kidneys, and might combine with oxalate to crystalize)
A better option would be a thiazide or thiazide-like.
Which cotransporter do thiazide and thiazide like drugs act on?
A Na/Cl cotransporter in the distal convoluted tubule
Name a thiazide drug
Hydrochlorothiazide
Name the thiazide like drugs
Indapamide, chlorthalidone
What are the adverse effects of thiazides/thiazide-like drugs?
–> Hypo Na, K
–> Hypotension
—> Increase in uric acid, glucose, and lipids
Which diuretics would you not prescribe to someone with dyslipidemia?
Loop diuretics + thiazides
–> adverse effects include increase in plasma lipids
What kind of diuretic would you not prescribe to someone with diabetes or who is prediabetic?
Thiazide
–> Adverse effects include increase in BGL
What are the potassium-sparing diuretics?
Spironolactone and eplerenone
What is another name for potassium-sparing drugs? Why?
Mineralocorticoid receptor antagonists
–> aldosterone receptor antagonists (inhibits NaCl secretion in distal convoluted tubule)
What are the adverse effects of eplerenone?
hyperkalemia
What are the adverse effects of spironolactone, in addition to hyperkalemia?
Has anti-androgen effect
–> Gynecomastia, menstrual irregularities, decreased libido
What are the arterial vasodilators? What are they used for? What are some precautions to using them?
Hydralazine, minoxidil
–> Used to treat hypertensive emrgencies / refractory
–> tend to increase heart rate and retention of Na and water, so used in combo with B-blockers and diuretics
What are the mixed (venous and arterial) vasodilators? What are they used for? What is a precaution with using them?
Sodium Nitroprusside
–> Used in hypertensive emergencies; rapid onset
–> Beware of cyanide poisoning
What are the a1 antagonists? What are they used for? What are their adverse effects?
Prazosin, terazosin, doxazosin
–> Reduce peripheral vasoconstriction
Used to treat HTN and BPH
Adverse effects
–> Orthostatic hypotension w reflex tachycardia
–> Na + water retentions
–> Fatigue
What adrenergic antagonist is used to treat hypertension is pregnant individuals? What is its mechanisms of action?
Labetalol
–> Inhibits alpha 1, beta 1, and beta 2 adrenergic receptors
What are some issues associated adherence strategies regarding antihypertensives?
–> There are no initial symptoms of the diease, but there are adverse effects of the medication
–> Long term treatment, longer dosing intervals helps with adherence
–> Often involves many drugs
What is the first line treatment for HTN?
Thiazides, ACEIs, ARBs, CCBs, B-blockers.
What adrenergic drug stimulates negative feedback on NA release, resulting in vasodilation? What is it used to treat? What are its adverse effects?
Clonidine
–> A2 agonist
Used to treat RfHTN
Adverse effects: sedation, dry mouth, depression
What noradrenaline synthesis inhibitor is used to treat HTN in pregnant women?
a-methyldopa, which is transformed into a-methyl-NA and stimulates a2 receptors.
