Antihypertensives Flashcards
Phentolamine is classified as a
alpha-adrenergic receptor antagonist
Is phentolamine competitive or noncompetitive
competetive (transient)
Is phentolamine selective or nonselective adrenergic blocker
nonselective
What effect does phentolamine have on vessels
vasodilation
As a consequence of blocking alpha receptors, what effect does this do to the heart rate when giving phentolamine
reflex tachycardia
Is Phenoxybenzamine a selective or nonselective alpha adrenergic blocker
nonselective
What are the two major differences between phentolamine and phenoxybenzamine
Onset slower than phentolamine
Elimination 1/2 time longer (24 hours) d/t irreversible noncompetitive blockade
Is Prazosin selective or nonselective
selective postsynaptic alpha 1 receptor blocker
Will prazosin evoke reflex tachycardia
No, bc no effect on alpha 2 receptors
What effect does prazosin have on arterioles and veins
dilates- decreases preload & afterload
What receptor (s) does Terazosin act upon
alpha 1 receptor blocker
What is terazosin used to treat
BPH
Beta-adrenergic blockers are classified as
nonselective and B1 selective (cardioselective)
What are the B1 selective blockers
Metoprolol
Atenolol
Acebutolol
Esmolol
Beta 1 receptor antagonists competively antagonizes the beta 1 receptors in the heart and what other cells
renin-secreting cells of the kidney
Between the B1 and B2 receptor antagonists, which is better for asthmatics or patient’s with RAD
Beta 1 receptor antagonist
Esmolol’s DOA is about 10 minutes because it is
rapidly hydrolyzed by plasma esterases
Name the two combined alpha/beta adrenergic antagonists
Labetalol
Carvedilol
what specific receptors does labetalol interact with
alpha1 and
nonselective beta adrenergic antagonist
What are the CV effects of labetolol administration
decreased systemic vascular resistance, decreased bp
What additional effect does labetalol have on beta 2 receptors
vasodilation (partial agonist)
Name the two centrally acting sympatholytic drugs discusses in class
Methyldopa
Clonidine
As an analog for L-dopa, Methyldopa is known as a
false transmitter
What is MOA of methyldopa
stored in adrenergic nerve vesicles, where is relplaces NE and is released by nerve stimulation to interact with postsynptic adrenorecptors
How is PVR reduced with methyldopa
via stimulation of central alpha adrenoreceptors
Methyldopa is primarily used for hypertension in which patient population
pregnant
Clonidine is classified as a
centrally acting alpha 2 adrenoreceptor agonist
What is clonidine’s MOA
stimulates alpha 2 adrenergic inhibitor neurons in the medullary vasomoter center
What principle effect does clonidine have
decreases SNS output from the CNS and increases ParaSNS tone
Decrease HR PVR and CO
What SE should you expect with centrally acting sympathomimetics
Sedation
Dry mouth
Withdrawl leading to HTN crisis
What are the Adrenergic Neuron-blocking agents
Trimethaphan
Reserpine
Guanethidine
What is the MOA of Guanethidine
Inhibits the release of NE from sympathetic nerve endings
What is reserpine’s MOA
blocks the ability of aminergic transmitter vesicles to take up and store biogenic amines
What is the MOA of Trimethaphan
Comptetitvely blocks nicotinic cholinorecetors on Postganglionic neurons
What does trimethaphan liberate
histamine
What are SE associated with trimethaphan
orthostatic hypotension constipation urinary retention gluacoma dry mouth
what are the ACE inhibitors
“PRILS”
What is the MOA of ACE inhibitors
blocks the conversion of angiotension 1 to angiotension II
What effect does ACE inhibitors have
decreased vasoconstrictive effects and decreased circulating levels of aldosterone
What other MOA does ACE inhibitors have
Blocks the breakdown of bradykinin
What is bradykinin
an endogenous vasodilator substance, which contributes to the anti HTN effects of the PRILS
What are the most common SE associated with the PRILS
COUGH
upper respirator congestion
rhinoorhea
Allergic-like symptoms
What is a potential life-threatening complication assoc. with ace-inhibitors
Laryngeal angioedema
ACE-inhibitors have what effect on renal function
decreases GFR, use carefully in patient’s with renal dx
What electrolyte dysfunction is likely with PRIL administration
hypekalemia
Enalapri is a ——– that is metabolized in the liver to its —- —–
prodrug
active form
therefore, DOA is longer
What are the Angiotesion II blockers
“SARTANS”
What specific receptor does ‘SARTAN’s” block
angiotensin II type 1 receptors
What are the calcium channel blockers
VeraPaMIL Ditiazem AmloDIPINE FeloDIPINE IsraDIPINE NicarDIPINE "PINE"
What effects do calcium channel blockers have
antianginal
antiarrhythmic
INHIBITION of calcium influx into arterial smooth muscle cells
List the drugs that release NO or cause it to be released by endothelium
Nitroprusside
Hydralazine
Name drugs that reduce calcium influx
Calcium channel blockers
Name drugs that cause hyperpolorization of smooth muscle membrane through opening of potassium channels
Minoxidil
diazoxide
Name the drug that activates dopamine receptors
Fenoldopam
Hydralazine works by
dilating arterioles but not veins
What is the consequence of hydralazine
causes reflex tachycardia
*bad for coronary dx patients or HF
What does hydralazines SE resemble
Lupus
*Arthralgia, myalgia, skin rash, and fever
What is minoxidil’s MOA
hyperpolorization of smooth muscle cells which leads to dilation of arterioles but not veins
Minoxidil is associated with
greater reflex sympathetetic stimulation and sodium and fluid retention than hydralazine
*as a consequence, it mus be used with beta blocker and loop diuretic
Nitroprusside works by
dilating both arterial and venous vessels
Nitroprusside is rapidly metabolized by
uptake into RBC with liberation of cyanide
Cyanide is converted to
thiocyanate, which is eliminated by the kidneys
Name a carbonic anhydrase inhibitor
acetazolamide
What is the MOA of acetazolamide
Blocks carbonic anhydrase activity at the proximal tubule of the kidney
What component in the H+ + HCO3- is lost with acetazolamide
HC03-
What happens to the sodium when HC03- is filtered
Sodium follows and leads to diuresis
What happens to the H+
It gets reabsorbed and combined with Cl- to offset the filtered HCO3-
*Leads to Hyperchloremic metabolic acidosis
What is acetazolamide used to treat
Glaucoma
What diuretic works on the ascending loop of henle
Furosemide
How does furosemide work
Inhibits Na/K/CL symporter resulting in lost of loss of sodium, potassium, and chloride ions. This leads to H20 loss and hypokalemia and hypocloremia
What is the indication for loop diuretic use
Acute pulmonary edema
Edematous CHF
HyperKalemia
Thiazide diuretics work on the
Distal Convoluted tubule by blocking the sodium chloride symporter.
Loss of sodium within the cells of the DCT cells leads to increased absorption of what electrolyte
Calcium via sodium/calcium ATpase pump
What is a common electrolyte abnormality of thiazide
HypoKalemic metabolic alkalosis
Name three potassium-sparing diuretics
Triamterene
Amiloride
Spironolactone
Potassium-Sparing diuretics work on
DCT
Spironolactone is considered a
aldosterone antagonist
*binds to cytoplasmic mineralocrticoid receptors on collectiong duct
Name a osmotic diuretic
Mannitol
What is significant about how mannitol is filtered
Excreted without tubular reabsorption or secretion
What effect does mannitol have
because it is not reabsorbed, the filtrate maintains its hyperosmolarity with prevents water reabsorption
What is mannitol indicated for
Increased intracranial pressure
Increased intraocular pressure
Prophlaxis against acute renal failure