Chapter 21: Adrenergic Antagonists Flashcards
What are the two major groups of adrenergic antagonists
- alpha-adrenergic blocking agents
- beta-adrenergic blocking agents
main therapeutic applications of the alpha blockade
- essential hypertension
- reversal of toxicity of alpha1 agonists
- benign prostatic hyperplasia (BPH)
- phenochromocytoma
- raynauds disease
what drug should be used to reverse the toxicity of alpha1 agonists
phentolamine
Benign prostatic hyperplasia (BPH) symptoms
dysuria, increased frequency of daytime urination, nocturia, urinary hesitancy, urinary urgency, a sensation of incomplete voiding, a reduction in the size and force of the urinary system
pheochromocytoma
- catecholamine secreting tumor (usually located in the adrenal medulla)
- principle cause of hypertension
pheochromocytoma treatment
surgery is the best option
raynauds disease
- peripheral vascular disorder
- vasospasms in the toes and fingers
- suppress symptoms by preventing alpha mediated vasoconstriction
adverse effects of alpha1 blockade
- orthostatic hypotension
- reflex tachycardia
- nasal congestion
- inhibition of ejaculation
- sodium retention (increased blood volume)
what is the most significant adverse effect associated with the alpha2 blockade
potentiation of reflex tachycardia
Prazosin [Minipress]
- competitive antagonist
- selective blockade of alpha1 adrenergic receptors
prazosin [Minipress] is administered
orally
prazosin [Minipress] antihypertensive effect peak in ______ and persist for ______
1-3 hours
10 hours
prazosin [Minipress] is excreted in
the bile
10% in the urine
prazosin [Minipress] half life
2-3 hours
prazosin [Minipress] adverse effects
- orthostatic hypotension
- reflex tachycardia
- inhibition of ejaculation
- nasal congestion
- ” first dose” effect
prazosin [Minipress] is used for
hypertension and BPH in men
Beta-Adrenergic Antagonists
propranolol [Inderal]
propranolol [Inderal] therapeutic applications
- angina pectoris
- hypertension
- cardiac dysrhythmias
- myocardial infraction (MI)
- heart failure
- hyperthyrodism
- migraine prophyaxis
- stage fright
- pheochromocytoma
- glaucoma
what drugs are considered standard therapy for heart failure
- carvedilol
- bisoprolol
- metoprolol
adverse effects of beta1 blockade
- bradycardia
- reduced cardiac output
- precipitation of the heart
- AV heart block
- rebound cardiac excitation
what are the early signs of heart failure
- shortness of breath, night coughs, swelling of the extremities
Adverse effects of beta2 blockade
- bronchoconstriction
- hypoglycemia from inhibition of glycogenolysis
propanolol blocks
beta 2 receptors
propranolol therapeutic uses
- hypertension, angina pectoris, myocardial infraction, prevention of migraine, “stage fright”
propranolol adverse effects
- bradycardia, AV heart block, heart failure, rebound cardiac excitation, bronchoconstriction, inhibition of glycogenolysis, possibly depression
propanolol drug interactions
- calcium channel blockers
- insulin
metoprolol blocks
beta1 receptors in the heart
metoprolol therapeutic uses
- hypertension, angina pectoris, heart failure, myocardial infraction
metoprolol adverse effects
- bradycardia, reduced cardiac output, AV heart block, rebound excitation
- minimal bronchoconstriction and interference with beta2 glycogenesis
metoprolol is safer than propranolol for patient with
asthma of a history or severe allergic reactions
how do labetalol and carvediol differ
block alpha-adrenergic receptors in addition to beta receptors
