Adrenergic Antagonists Flashcards
Name the 4 α-antagonists.
Phentolamine, phenoxybenzamine, prazosin, terazosin
Name the 2 non-selective α-antagonists. Which one is a non-competitive inhibitor?
Phentolamine and phenoxybenzamine; phenoxybenzamine is non-competitive and forms covalent bonds with the receptors
Name the 2 α1-selective antagonists.
Prazosin and terazosin
What is a common side effect of all the α-antagonists? What is a common side effect of only the non-selective α-antagonists?
Postural hypotension; inhibition of ejaculation
What 3 conditions are phentolamine and phenoxybenzamine used to treat because they inhibit both α1 and α2 receptors?
Pheochromocytoma, Raynaud’s, and frostbite
What 2 conditions are prazosine and terazosin used to treat?
Primary hypertension and BPH (benign prostatic hypertrophy)
Explain the selectivity of the 1st, 2nd, 3rd “A” and 3rd “B” generation β-antagonists.
1st and 3rd “A”: non-selective (affect β1 and β2)
2nd and 3rd “B”: β1-selective
Name all 8 of the β-selective antagonists.
Propranolol, timolol, metoprolol, atenolol, bisoprolol, carvedilol, labetalol, betaxolol
Name the 2 non-selective 1st generation β-antagonists. Which one is the standard to which all new β-antagonists are compared?
Propranolol and timolol; propranolol is the old standard
Name the 3 β1-selective, 2nd generation β-antagonists.
Metoprolol, atenolol, bisoprolol
Name the 3 3rd generation β-antagonists. Which are “A” and which is “B”?
Carvedilol and labetalol: “A”
Betaxolol: “B”
What 3 conditions is propranolol used to treat? What other generation of β-antagonists is used to treat all of these conditions?
Angina, hypertension, arrhythmias; the 2nd generation β-antagonists (β1-selective: metoprolol, atenolol, bisoprolol)
Name the only β-antagonist not used to treat hypertension. What is it used for instead?
Timolol; glaucoma
Which β-antagonists can be used to treat congestive heart failure? Name the 2 generations and the 6 specific drugs.
2nd and 3rd gen β-antagonists: metoprolol, atenolol, bisoprolol, carvedilol, labetalol, betaxolol
List all 4 conditions that the 2nd generation β-antagonists are used to treat.
Hypertension, angina, arrhythmia, congestive heart failure
What is the major side effect of using any β-antagonist? Which receptor mediates this effect?
Bradycardia, due to β1 antagonism (all β-blockers affect β1)
Besides bradycardia, list 3 side effects of β-antagonists, and state which drugs are associated with each effect.
Bronchoconstriction: 1st gen
Sexual dysfunction: 1st and 2nd gen
Fatigue: 3rd gen “A”
The 3rd generation “A” β-antagonists have an “additional action.” What is this action and what receptor mediates it?
Vasodilation, due to α1-receptor antagonism
Name the 6 miscellaneous adrenergic affectors: 1 indirect acting agonist, 2 street drugs, and 3 nerve ending blockers.
Tyramine, amphetamine, cocaine, guanethidine, reserpine, and α-me-tyrosine
Which adrenergic drug should not really be in this deck because it is an indirect agonist and not an antagonist? Describe what kind of protein it binds to and the effect.
Tyramine; binds an exchange transporter and goes into the cell while norepi comes out, increasing cytoplasmic release of norepi
Describe how amphetamine acts in the synaptic cleft and what 2 diseases it is used to treat (boredom is not a disease).
Increases norepinephrine release; treat ADHD and narcolepsy
Describe how cocaine acts in the synaptic cleft and give 2 medical uses for it.
Decreases norepinephrine reuptake; used for vasoconstriction and as a local anesthetic
Give 4 side effects of using amphetamine or cocaine.
Hypertension, insomnia, anxiety, and arrhythmias. (the table doesn’t technically list hypertension for cocaine but close enough)
Name the 3 adrenergic nerve ending blockers. Which is the only one used clinically in the U.S.? What is it used for?
Guanethidine, reserpine, and α-me-tyrosine; only α-me-tyrosine is used in the U.S. for pheochromocytoma
