Pharmacology of Antihypertensive Drugs Flashcards
Beta blocker generations
1st - non selective
2nd - beta 1 receptor
Third - with additional action
1 - proponalol/nadalol
2 - atenolol/metoprolol
3 - carvedilol, labetalol, nebivolol
Cardvedilol
Labetalol
Nebivolol
additional actions
Carv - blocks alpha, antioxdant, reduce cardiac hypertrophy
Blocks alpha
Vasodilator
Consequences of beta blockade
Dec in contractile force
Dec in HR
Dec renin release and AT2
Therefore dec force, rate and renin secretion
HTN and beta blockers
Due to beta 1 blockade and dec in CO, HR, and renin
Beta blockade in SVT and ischemic HD
Blocks SA and AV nodal beta receptors
Dec force and ratre of contraction so dec myocardial oxygen consumption
Beta blockade in post MI, HF
MI - prevent reinfarction…dec in oxygen consumption, work of the heart, and blocks arrhtyhmias
HF - blockade elevated symp, hypertrophic growth and free rad formation
Side effects of beta blockrs
Bradycardia and AV nodal blockade
Dec in contractility
Hypotension
Sedation, fatigue, lassitude
Beta2 blockade side effects
Specific to 1st gen
Airway dz and peripheral vascular dz
Calcium channel blockers
Amlodipine/nifedipine
First line for HTN…arterial vasodilators that dec PVR
CCBs MOA
1) slow HR and lower BP
2) only verapamil and diltizaem act at SA node to slow down
3) ALL CCBs vasodilate
Hydralazine
Second line HTN tat is vasodilator
Reserved for mod to severe
Hydralazine SE
Genetic based - inactivated by N-acetylation and can produce a lupus like syndrome
Likelihood of lupus-like syndrome increeased in the slow acetylator population
Vasodilator SE - typical effects are hypotension, headache, tachycardia
Minoxidil
Arterial vasodilator that stimulates an outward K+ channel resulting in hyperpolarizaiton of vascular smooth muscle cell
Minoxidil use and SE
Mod to severe HTN
Hypotension, headache, tachy and hair grwoth
ACEI and ARBs uses and cautions
1st line for HTN and HF
Lisinopril and losartan
Stronger with ACEI
Caution in pregnant
ACEI side effect
Bradykinin induced cough
ACEI and ARB side effect
Hyperkalemia due to aldosterone inhibion
Angioedema, loss of taste, hypotension
Alikerin
Binds to reinin and blocks catalytic activity…AT 2 will be decreased
Can be used alone or with others
Do not use in diabetics
Thiazide diuretics use
1st line for HTN
HCTZ and chlorthalidone
Intiially reduce plasma volume…LT use with dec in PVR
SE and toxocity of thiazeise
hypotension and volume depletion
Impotence
Hypokalemia - increase likelihood of vent arrhythmias and potentiate arrhythmogenic action of toher drugs…can produce muscle weakness and drowsiness
Some HS
Drug interactions of thiazises
NSAIDs and lithium
K+ sparing
Amiloride and triamteren - direct Na channel inhibs
Aldosterone antagonists - spironolactone and eplernone
K+ sparing uses
Not usually used alone to tx HTN
USed to minimize K+ loss cuased by other diuretics
Aldosterone antag for HF
K+ sparing toxicity
Hyperkalemia
Spirnolactone - hynecomastia, dec libido and impotence in men and menstural probs in women
Clonidine
Alpha 2 receptor agonist that dec sympathetic outflow and therefore dec BP
