Adrenergic Drugs Flashcards
name the inhibitors of catecholamine storage
- amphetamine
- pseudoephedrine
amphetamine
inhibitor of catecholamine storage
- moa
- releases NE and dopamine (DA) from nerve terminals
- block reuptake of NE by blocking NE transporters
- overall increase of NE levels in synaptic cleft in sympathetic NS and in CNS
- clinical use
- treatment of ADHD
- side effect
- drug abuse
- increased DA in brain = paranoia + hallucinations
pseudoephedrine
inhibitor of catecholamine storage
- moa
- releases stored NE from nerve terminals
- α and β agonist activity
- clinical use
- treatment of nasal and sinus congestion
- side effect
- CNS stimulation
name inhibitors of catecholamine reuptake
- cocaine
- imipramine
cocaine
inhibitor of catecholamine reuptake
- moa
- inhibits NE transporter
- clinical use
- previous use = local anesthetic
- side effect
- drug abuse
- leads to depletion of dopamine which triggers cravings
imipramine
inhibitor of catecholamine reuptake
- moa
- blocks NE transporter
- clinical use
- treats mild depression
- side effect
- postural hypotension
- tachycardia
iproniazid (discontinued now)
inhibitor of catecholamine metabolism
- moa
- blocks metabolism of NE in the nerve terminals
- MAOIs increase NE levels which provide more NE available for release into synaptic cleft
- clinical use
- treats depression
- side effect
- must not eat food containing tyramine (fermented foods) since is causes release of NE from nerve terminals
- can cause massive vasoconstriction leading to “hypertensive crisis” which can result in a stroke
- must not eat food containing tyramine (fermented foods) since is causes release of NE from nerve terminals
name the α agonists
- oxymetazoline
- α1 and α2 agonist
- phenylephrine
- α1 agonist
- clonidine
- α2 agonist
describe the moa of α agonists
- causes vasoconstriction that increases the total peripheral resistance and increases BP
- no effect on heart but due to causing an increased BP will cause reflex bradycardia
clinical usage of oxymetazoline
- nasal decongestant (relief due to nasal vasoconstriction)
- ophthalmic hyperemia (vasoconstriction of the conjunctiva)
- eye drops relieve redness and itchy eyes
clinical usage of phenyleprhine
α1 agonist
- emergency treatment of shock
- nasal decongestant (relief due to vasoconstrictor effect on nasal mucosa
- side effect: hypertension
clinical usage of clonidine
α2 agonist
- treatment of hypertension
- use in treatment of symptoms associated with drug withdrawal
name the β blockers
- propranolol
- non-selective β blocker
- atenolol
- selective β1-blocker
- pindolol
- partial β1 agonist
- reduces the effect of endogenous NE at β1 receptors
- partial β1 agonist
name the function of β blockers
- all β blockers are competitive antagonists
- decreases HR and CO
- decrease SA and AV nodal activity
clinical usage and side effects of propranolol
- clinical use
- treatment for hypertension and angina
- side effect
- non-competitive, thus more severe sedation, bronchodilation and dyspnea
- bronchoconstriction (COPD + ashtma patients)
- metabolic disturbances (diabetes patients)
- due to decreased glycogenolysis and glucagon secretion
clinical use and side effects of atenolol
selective β1-blocker
- clinical use
- treatment for hypertension and angina
- reduces blood voluma via decreased renin production
clinical usage and side effects of pindolol
partial β1 agonist
- treatment for hypertension in patients with bradycardia or low cardiac reserve
- side effects:
- bronchoconstriction
- metabolic disturbances
- partial agonists are weak antagonists, thus weak stimulatory effects on both β1 and β2 receptors
name α antagonists
- phenoxybenzamine
- α1 and α2 antagonist
- irreversible and non-competitive
- phentolamine
- α1 and α2 antagonist
- reversible and competitive antagonist of NE/Epi
- tamsulosin
- α1 antagonist
what is the moa of α antagonists
- prevent sympathetically mediated vasoconstriction and hence cause vasodilation and profound fall in BP
name clinical use and side effects of phenoxybenzamine
α1 and α2 antagonist
- given prior to removal of tumor surgically as to avoid hypertensive crisis
- given for long-term management of pheochromocytoma where surgery not an obvious option
- side effect:
- postural hypotension
- nasal congestion
- failure of ejaculation
describe clinical use of phentolamine
- treatment of pheochromocytoma
- preferable to phenoxybenzamine since it is reversible
name clinical use and side effect of tamsulosin
α1 antagonist
- used to treat benign prostatic hyperplasia
- relaxes internal sphincter (trigone muscle) of bladder and relaxes smooth muscle associated with prostate gland which relieves urinary hesitancy
- α1A subtype of the α receptor preferentially expressed in genitourinary smooth muscle
- side effect: postural hypotension, nasal congestion, less reflex tachycardia
name clinical use and side effect of prazosin
- used to reduce blood pressure
- side effects: marked postural hypotension (particularly after first dose)
name the β agonists
- dobutamine
- β1 agonist
- albuterol
- β2 agonist