Adrenergics Flashcards
blocks L-type calcium channels at higher doses
carvedilol
what receptors does labetalol affect?
α1 and β1/2
which adrenergic neuron blocker can enter the CNS?
guanadrel
therapeutic use of carvedilol
- hypertension
- chronic heart failure
- acute MI
which therapeutic use of propranolol is not shared by atenolol?
migraine prophylaxis
what does reserpine treat?
essential HTN, rarely used
decreases vascular tone in resistance (arterioles) and capacitance (veins) beds
prazosin
how is phentolamine administered?
orally
competitive antagonist of α1 and both β receptors
labetalol
carvedilol
what receptors does timolol affect?
non-selective β antagonist
this β1 antagonist does not penetrate the CNS, so it has less CNS side effects
atenolol
this α1 receptor antagonist is not approved for threatment of HTN
tamsulosin
how is prazosin administered?
orally
what receptors does phenoxybenazmine affect?
irreversible α1 and α2 antagonist
therapeutic use of labetalol
- essential hypertension (oral)
- hypertensive emergencies (IV)
orally active α1 recepotr antagonist with some selectivity for α1A verses α1B subtypes
tamsulosin
what is tamsulosin used to treat?
BPH with little effect on blood pressure (less propensity for orthostatic hyptotension)
adrenergic neuron blockers
guanethidine
guanadrel
inhibit NE release by taking its place in vesicles
produces a favorable lipid profile by decreasing LDL and increases HDL
prazosin
what drug causes first dose phenomenon?
prazosin
clinical uses of phenoxybenzamine
- pheochromocytoma
- reverse or shorten duration of soft-tissue anesthesia
what receptors does tamsulosin affect?
α1 (mostly α1A) antagonist
what receptors does metoprolol affect?
β1 antagonist
at low doses is more selective at blocking the β1 receptor by 10-fold
metoprolol
how is tamsulosin administered?
orally
prwhat receptors dose prazosin affect?
α1 antagonist
describe propanolol’s withdrawal syndrome
supersensitivity to β adrenergic stimulation which may cause angina, arrhythmias, or infarction
what receptors does atenolol affect?
β1 antagonist
also has anti-oxidant properties and anti-inflammatory effects
carvedilol
therapeutic use:
- essential hypertension (oral)
- hypertensive emergencies (IV)
labetalol
clinical uses of phentolamine
- HTN
- pheochromocytoma
- reverse or shorten duration of soft-tissue anesthesia
which drugs reverse or short the duration of soft-tissue anesthesia produced by combined local anesthetic and sympathomimetics?
phentolamine
phenoxybenzamine
which drug masks the symptoms of hypoglycemia?
propranolol (and related drugs)
treats shock
NE
DA
phenylephrine
which drug can cause sedation, impotence, and nightmares?
propranolol
what drugs share therapeutic uses with propranolol?
atenolol
metoprolol
timolol
orally active, once a day dosing
atenolol
how is atenolol administered?
orally active, once a day dosing
β1 receptor antagonists
metoprolol
atenolol
what is distinct about timolol?
treats wide angle glaucoma
which of the 2 β blockers that we need to know treat heart failure?
metoprolol
carvedilol
what receptors does phentolamine affect?
α1 and α2 antagonist
therapeutic use:
- chronic heart failure
- hypertension
- acute MI
carvedilol
what do guanethidine and guanadrel treat?
hypertension (limited use)
orally active pro-drug
methyldopa
how is phenoxybenzamine administered?
orally
how are guanethidine and guanadrel administered?
orally
side effects of phentolamine and phenoxybenzamine?
- tachycardia
- edema (salt/water retention)
- orthostatic hypotension
side effects of propranolol
- cardiac depression, bradycardia/heart block
- may increase airway resistance
- mask symptoms of hypoglycemia
- sedation, impotence, nightmares
how is labetalol administered?
orally (HTN) & IV (HTN emergencies)
used with local anesthetics to increase duration of action
phenylephrine
epinephrine
used in emergencies to stimulate heart rate during bradycardia or heart block
isoproterenol
major therapeutic uses of propranolol
- HTN
- angina
- cardiac arrhythmias due to excess catecholamines
- acute MI
- pheochromocytoma
- migraine prophylaxis
how is resperine administered?
orally
why is reflex achycardia less problematic in prazosin usage?
little blockage of pre-synaptic α2 receptors - minimal increase in CO
what receptors does carvedilol affect?
α1 and β1/2
which adrenergic neuron blocker is polar and cannot enter the CNS?
guanethidine
this drug enters the CNS and may cause depression, suicide, sedation
reserpine
favors blockade of α1A in prostate
tamsulosin
what receptors does propranolol affect?
non-selective β antagonist
propranolol should be used with caution with what kinds of patients?
- asthma
- congestive heart failure
- bradyarrhythmias, AV block
- insulin-dependent diabetes prone to hypoglycermic episodes
- hypotension
- vasospastic angina
how is phenylephrine administered?
nasal spray or orally
ophathalmic
