Chapter 4 Cardiovascular and hematology drugs - alpha and beta blockers Flashcards
prazozin (minipress)
terazosin
doxazosin (cardura)
a adrenergic antagonists
- peripheral alpha 1 adrenergic antagonist
- dilates both arteries and veins
indication
* HTN and HTN w/ CHF
effects
* hypotension (postural hypotension on 1st dose is sudden and severe)
* sodium depletion (d/t diet or diuretic therapy caused by diet or diuretic therapy) => worsens hypotensive episodes
* edema
* dry mouth
* congestion
* headache
* nightmares
* sexual dysfunction
* lethargy
interaction
* phenobarbital shorten this drug’s half life
* enhance other antihypertensive
patient should be lying down and observed for at least 2 hours after initial dose
labetalol (trandate)
carvedilol (coreg)
mixed a and b antagonist
blocks a1, b1, and b2
* achieves lower blood pressure (a1) without reflex tachycardia (b1 blockade)
indication
* HTN
effects
* further suppresses failing heart
* fatigue
* impotence
* diarrhea
* numbness
* orthostatic hypotension
PO/IM/IV
reduce carvedilol dose w/ renal or liver dysfunction
contraindicated
* asthma or bradycardia
interactions
* labetalol — myocardial depression w/ halotane, blocks b-agonist induced bronchodilation
* carvedilol — inc effects/toxicity of CCB, clonidine, digoxin, sinulin, antidiabetics
atenolol (tenormin)
betaxolol (kerlone)
carteolol (cartrol)
penbutolol (levatol)
bisoprolol (zebeta)
metoprolol (lopressor)
b adrenergic antagonists
- prefers to block b1 — lower HR and output + dec renin release
- less bronchoconstriction than agents which bind to b2 receptors!
indication
* starting therapy for mild to moderate HTN
effects
* worsens failing heart
* CNS sedation
* depression
Decreased dose w/ renal dysfunction
contraindication
* severe diabetes
* bradycardia
* partial heart block
* severe heart failure
* asthma
* emphysema
interaction
* all beta blockers enhance digoxin and lidocaine!
metaprolol may be inc w/ verapamil, cimetidine, or oral contraceptives
acebutolol (sectral)
b adrenergic antagonist
- intrinsic sympathomimetic activity as well as b1 blocking activity
indication
* mild-moderate HTN
effects
* worsens failing heart
* CNS sedation
* depression
contraindications
* severe diabetes
* bradycardia
* partial HB
* severe HF
* asthma
* emphysema
interactions
* all beta blockers enhance effects of digoxin and lidocaine
esmolol (brevibloc)
b adrenergic antagonist
- prefers to block b1 — lower HR and output + dec renin release
- less bronchoconstriction than agents which bind to b2 receptors!
indication
* cardiosuppression in acute MI and unstable angina
effects
* worsens failing heart
* CNS sedation
* depression
contraindications
* severe diabetes
* bradycardia
* partial HB
* severe HF
* asthma
* emphysema
propranolol (inderal)
nadolol (corgard)
timolol
b adrnergic antagonist
- blocks b1 and b2
- dec HR and output + decreased renin release
- bronchoconstriction vai antagonism of b2 receptors
HTN
effects
* transient HTN d/t b2 antagonism (which dilate large arteries
* reflex response to decreased cardiac output
* bronchospasm
* worsens failing heart
* CNS sedation
* depression
Good CNS penetration (propranolol)
Poor CNS penetration / decrease dose w/ renal dysfunction (nadolol)
Enters CNS w/ fewer side effects than propranolol (timolol)
contraindications
* severe diabetes
* bradycardia
* partial HB
* severe HF
* asthma
* emphysema
interaction
* cimetidine inc serum concentration of propranolol
* all beta blockers enhance effects of digoxin and lidocaine
abrupt d/c can cause rebound HTN, tachycardia — inc risk of stroke, angina, arrhtyhmias, infarction
pindolol (visken)
- some intrinsic sympathomimeitc activity as well as b1 and b2 blocking activity
indication
* cardiosuppression in acute MI and unstable angina
effects
* intrinsic sympathomimetic activity decreases likelihood of rebound HTN (by dilating large arteries via b2) or bronchospasm
- all beta blockers enhance effects of digoxin and lidocaine
