Adrenoceptor Blockers Flashcards
alpha-non-selective blocker
IRREVERSIBLY blocks a1 > a2 receptors
used for pheochromocytoma (pre-surgical)
side effects: ORTHOSTATIC HYPOTENSION, REFLEX TACHYCARDIA, GI irritation, myocardial ischemia
forms covalent bonds with alpha receptors (effects last several days)
Phenoxybenzamine
alpha-non-selective blocker
REVERSIBLY blocks a1 > a2 receptors
used for pheochromocytoma (pre-surgical), REBOUND HYPERTENSION
antidote to a1 agonist overdose
side effects: orthostatic hypotension, reflex tachycardia, GI irritation
Phentolamine, Tolazoline
selective alpha 1 blocker
used for benign prostatic hyperplasia, hypertension
side effects: first dose orthostatic hypotension, reflex tachycardia
Prazosin
Doxazosin, Terazosin, Tamsulosin, Silodosin, Alfuzosin
most selective for prostatic smooth muscle
Tamsulosin
pharmacologic advantage of alpha 1 selectivity
reflex tachycardia is less common and less severe
non-selective beta blocker
blocks B1 and B2
blocks sympathetic effects on heart and BP
reduces renin release
used for angina prophylaxis, hypertension, arrhythmias, migraine, performance anxiety, hyperthyroidism
side effects: bronchospasm, AV block, heart failure, CNS sedation, erectile dysfunction
Propranolol
Pindolol, Timolol, Labetalol, Carvedilol, Nadolol, Levobunolol, Metipranolol
masks symptoms of hypoglycemia in diabetics
Propranolol
Pindolol, Timolol, Labetalol, Carvedilol, Nadolol, Levobunolol, Metipranolol
has combined alpha and beta blockade
may be use in pheochromocytoma
carvedilol and labetalol
intrinsic sympathomimetic activity
partial agonist activity
less likely to cause bronchospasm
Acebutolol, Pindolol
Carteolol, Bopindolol, Oxprenolol, Celiprolol, Penbutolol
intrinsic sympathomimetic activity
Acebutolol, Pindolol
local anesthetic activity
membrane-stabilizing activity
disadvantage when beta-blockers are used topically in the eye: decreases protective reflexes, increases risk of corneal ulceration
absent from timolol and betaxolol
hence useful for glaucoma
beta blocker with longest half life
nadolol
b1 selective blocker
blocks sympathetic effects on heart and BP
used for angina, hypertension, heart failure
side effects: less bronchospasm, AV block, heart failure, CNS sedation, erectile dysfunction
Atenolol
Betaxolol, Esmolol, Acebutolol, Metoprolol, Alprenolol, Nebivolol
b1 selective blocker
used for supraventricular tachycardia
has shortest half life
esmolol
masks symptoms of hypoglycemia in diabetics
Atenolol
Betaxolol, Esmolol, Acebutolol, Metoprolol, Alprenolol, Nebivolol
