Antihypertensives Flashcards
RAAS System
- low BP –> renin secretion
- renin converts angiotensinogen –> angiotensin I (inactive)
- angiotensin-converting enzyme (ACE) turns angiotensin I –> angiotensin II (active)
- angiotensin II –> vasoconstriction, release of aldosterone & ADH
- aldosterone & ADH –> Na & H2O retention (& K excretion)
- increased BP
How is BP regulated by body?
Kidneys via RAAS
What hormones are involved with BP?
ADH, ANP, BNP, RAAS hormones
Risk factors for HTN
- excess saturated fat & carbs in diet
- alcohol use
- obesity
How do African Americans vs Asian Americans respond to BP meds?
African Americans hyposensitive
Asian Americans hypersensitive
Non-pharmacologic methods of HTN control
- stress reduction
- exercise
- salt reduction
- decrease alcohol consumption
- smoking cessation
Define inotrope, chronotrope, & dromotrope
- inotrope - contractility
- chronotrope - rate/rhythm
- dromotrope - speed of electricity conduction through AV node
Types of antihypertensives?
seven
- Diuretics
- Alpha blockers
- Angiotensin converting enzyme (ACE) Inhibitors
- Angiotensin receptor blockers (ARBs)
- Anti-anginals (NTG)
- Beta blockers (BB)
- Calcium chanel blockers (CCB)
Beta Blockers for HTN
- -lol
- vasodilation –> decreased HR, BP
- can cause bronchospasms, rebound HTN
- antidote is glucagon
- monitor kidney labs (& liver)
Selective HTN beta blockers
B1 receptors
metoprolol, atenolol, esmolol
Non-selective HTN beta blockers
B1 & B2 receptors
labetalol, carvedilol, prapanolol
Central-acting alpha 2 agonists for HTN
- sympatholytic
- good for non-cardiac HTN
- stimulates alpha receptors in CNS to inhibit vasoconstriction
- decreases cardiac output, epi/norepi, and renin release
- don’t use w/ impaired liver or HF
- rebound HTN, Na & H2O retention
methyldopa, clonidine (patch for 7 days), guanfacine
Alpha adrenergic blockers for HTN
- -sin
- decrease sympathetic vasoconstriction –> decreased afterload, increase renal blood flow
- ortho. hypo., edema, nasal congestion
doxazosin, prazosin, terazosin
Adrenergic neuron blockers for HTN
- block & decrease norepi release –> lower BP
- most potent, last drug of choice
- ortho. hypo., pseudoparkinsonism
reserpine
Alpha 1 & Beta 1 adrenergic blockers for HTN
- -alol/-olol
- blocks A1 & B1 receptors
- effect on A1 > than B1 –> greater decrease in BP, less incidence of bradycardia
- hypotension, bradycardia, large doses can block B2 (bronchoconstriction)
- monitor for fluid retention/weight gain
labetalol, carteolol
Direct-acting arteriolar vasodilators for HTN
- relax smooth muscles of blood vessels, esp arteries –> vasodilation & decreased BP
- hydralazine –> IV PRN for periodic HTN (mod to severe HTN)
- minoxidil –> kidney pts (mod to severe HTN)
- nitroprusside –> acute HTN emergency
- tachycardia, palpitations
Angiotensin-converting enzyme (ACE) inhibitors
- -pril
- inhibits formation of angiotensin II & blocks release of aldosterone
- Dry cough, hyperkalemia, hyponatremia, angioedema (vascular tissue swelling)
- African Americans & older adults don’t respond to ACEIs alone
- don’t use salt substitutes w/ potassium
Angiotensin II receptor blockers (ARBs)
- -tan
- prevent release of aldosterone by blocking angiotensin II
- hyperkalemia, hyperglycemia, heartburn
losartan, valsartan, irbesartan
Direct renin inhibitor
- binds with renin –> reduction of angiotensin I & II, aldosterone levels
- hyperkalemia, Stevens-Johnson syndrome
- not proven effective in African American population
Calcium channel blockers
- -pine
- slow calcium channels in myocardium & vascular smooth muscle cells –> vasodilation
- dizziness, peripheral (dependent) edema, bradycardia, hypotension, palpitations
amlodipine, verapamil & diltiazem only two w/ different endings
Antianginals/Nitrates
- produce vasodilation, decrease pre/afterload, reduce myocardial O2 use
- dilate arterial & venous vessels, specifically coronary arteries
- used for angina, MIs too
- hypotension, headache
sublingual nitroglycerin
