Andrenergics Flashcards
Metaraminol
- Adrenergic agonist – a1 selective (a1»_space; a2)
- Long acting (no OH) B1/A1 receptor stimulant - vasoconstriction, mydriasis, piloerection, increased cardiac output, inhibit GI motility
- Hyperactive sympathetic symptoms
- Vasopressor (hypotension – not shock)
Methoxamine
- Adrenergic agonist – a1 selective
- Vasoconstriction, mydriasis, piloerection, increased cardiac output, inhibit GI motility
- Hyperactive sympathetic symptoms
Phenylephrine
- Adrenergic agonist – a1 selective (a1 = a2)
- Long acting (no OH) - vasoconstriction, mydriasis, piloerection, increased cardiac output, inhibit GI motility
- Hyperactive sympathetic symptoms
- Nasal decongestant, vasopressor, mydriatic, overcome hypotension, local vasoconstrictor
- a-methyldopa
- Clonidine
- Guanabenz
- Adrenergic agonist – a2 selective
- Inhibit NE release by nerve terminal - decreased total peripheral resistance, HR, and cardiac output)
- Sedation, xerostomia, anorexia, fluid retention, vivid dreams, CNS stimulation
- Can be used for hypertension
Amphetamine
*Adrenergic agonist – mixed a/b, NE releasing agent *Block NE reuptake and reverse transport to release intraneuronal NE (a1 and B1 receptors) *Hyperactive sympathetic symptoms *Vasopressor
Ephedrine
*Adrenergic agonist – mixed a/b,
NE releasing agent
*Long acting (no OH), directly stimulates a1 and B1 receptors - relax bronchial smooth muscle (B2), elevation of cardiac output and arterial pressure
*Hyperactive sympathetic symptoms
*Vasopressor, mydriatic, nasal decongestant, CNS stimulant, chronic orthostatic hypotension, stress incontinence
Dipivefrin
- Adrenrgic agonist – mixed a/b
- Hyperactive sympathetic symptoms
- Open angle glaucoma
Epinephrine
*Adrenergic agonist – mixed a/b – a1 = a2, B1 = B2
*B receptors are 10x more sensitive than A – low dose will see only B effects
Relax bronchial smooth muscle, very potent vasoconstrictor and cardiac stimulant, decreased total peripheral resistance (B2)
*Hyperactive sympathetic symptoms
*Anaphylactic shock, severe allergic reactions, open glaucoma, slow profuse bleeding, increase systolic BP (B1/A1 effects), heart block/cardiac arrest
Norepinephrine
- Adrenergic agonist – mixed a/b – a1 = a2, B1»B2
- Vasoconstriction to increase peripheral resistance (a1 receptors) and increase cardiac output (B1 receptors)
- Hyperactive sympathetic symptoms
- Vasopressor (shock) (IV only)
Dobutamine
- Adrenergic agonist – B1 selective
- Increase force cardiac contraction, increase cardiac output
- Hyperactive sympathetic symptoms
- Congestive heart failure, cardiogenic shock following MI
Isoproterenol
- Adrenergic agonist – B non-selective
- Very potent B agonist with very little a activity - relax bronchial smooth muscle (B2 stimulation), cardiac stimulant (B1), vasodilator
- Hyperactive sympathetic symptoms
- AV block, asthma – increase in cardiac output and decreased MAP with vasodilation
Albuterol
- Adrenergic agonist – B2 selective
- Skeletal muscle vasodilation, smooth muscle relaxation
- Hyperactive sympathetic symptoms
- Bronchial asthma
Metaproterenol
- Adrenergic agonist – B2 selective
- Skeletal muscle vasodilation, smooth muscle relaxation
- Hyperactive sympathetic symptoms
- Vasopressor (hypotension – not shock), bronchial asthma
Terbutaline
- Adrenergic agonist – B2 selective
- Relax bronchial smooth muscle
- Hyperactive sympathetic symptoms
- Asthma, relax pregnant uterus
Bromocriptine
- Adrenergic agonist – dopamine (D2)
- Decreases neurotransmitter release
- Postural hypotension, cardiac arrhythmias
- Anti-parkinson agent with CNS effects
Dopamine
- Adrenergic agonist – dopamine, D1 = D2
- Vasoconstriction (a1), increase cardiac output (B1), dilate renal blood vessels (DA1)
- Hyperactive sympathetic symptoms
- Vasopressor, very effective for shock, cardiogenic shock following MI
Doxazosin
- Adrenergic antagonist – a1 selective»_space;» a2
- Vasodilation
- Excessive dilation
- Urinary obstruction
Prazosin
- Adrenergic antagonist – a1 selective»_space;» a2
- Competitive reversible - little or no tachycardia due to a1 selectivity, vasodilation
- Hypotension
- Hypertension – oral – 12 hours – urinary obstruction
- Tamsulosin
- Terazosin
- Adrenergic antagonist – a1 selective»_space;» a2
- Vasodilation
- Excessive dilation
- Urinary obstruction
Phenoxy-benzamine
- Adrenergic antagonist – a non-selective a1 > a2
- Noncompetitive irreversible – alkylates a1 and a2 (can’t bind NE) and inhibits NET (NE can’t reuptake) - postural hypotension and tachycardia (reflex activation of adrenergic nervous system)
- Hypotension
- Lasts about 24 hours – oral or IV – pheochromocytoma (management of hypertension post-op)
Phentolamine
- Adrenergic antagonist – a non-selective a1 = a2
- Competitive reversible – inhibits both a1 and a2 - vasodilation, but increased NE release (increased cardiac output and tachycardia)
- Dirty drug – activity with muscarinic receptors and histamine
- Pheochromocytoma – preoperative management of hypertension/ inoperative or metastatic tumors
Labetalol
- Adrenergic antagonist – mixed a/b – B1 = B2 > a1 > a2
- Inhibit cardiac output, causes vasodilation
- Cardiac failure
- Anti-hypertensive
Atenolol
- Adrenergic antagonist – B1 selective»_space;» B2
- Cardiac specificity - 6-9 hours – inhibit cardiac output
- Fewer CNS effects – inability to cross BBB – caution with asthma and COPD – cardiac failure
- Effective anti-hypertensive w/o constriction of bronchial smooth muscle (asthma)
Betaxolol
- Adrenergic antagonist – B1 selective»_space;» B2
- Cardiac specificity - 14-22 hours – inhibit cardiac output
- Caution use with asthma/COPD – cardiac failure
- Effective anti-hypertensive w/o constriction of bronchial smooth muscle (asthma), open glaucoma
Metoprolol
- Adrenergic antagonist – B1 selective»_space;» B2
- Cardiac specificity – effective prophylactic agent to prevent recurrence of MI - 3-4 hours – inhibit cardiac output
- Caution use with asthma/COPD, ataxia and dizziness – cardiac failure
- Effective anti-hypertensive w/o constriction of bronchial smooth muscle (asthma)
Nadolol
- Adrenergic antagonist – B nonselective B1 = B2
- 14-24 hours – inhibits cardiac output
- Fewer CNS effects – inability to cross BBB – cardiac failure
- Antihypertensive
- Carteolol
- Levobunolol
- Metipranolol
- Adrenergic antagonist – B nonselective
- Reduce aqueous humor production – block B1 on ciliary body
- Open angle glaucoma
Pindolol
- Adrenergic antagonist – B nonselective B1 = B2
- 3-4 hours – inhibits cardiac output
- Cardiac failure
- Antihypertensive
Propranolol
- Adrenergic antagonist – B nonselective B1 = B2
- 3-6 hours – inhibits cardiac output
- Ataxia and dizziness, cardiac failure
- Antihypertensive, anti-arrhythmic, angina pectoris, migraines, prophylactics to prevent MI
Timolol
- Adrenergic antagonist – B nonselective B1 = B2
- 4-5 hours – inhibits cardiac output
- Cardiac failure
- Prophylactics to prevent MI, antihypertensive, angina pectoris, decrease IOP (glaucoma)
a-methyldopa
- False transmitter
- Enters both PNS and CNS – replaces DOPA in synthetic pathway (a-methyl NE is made) - Potent stimulation within brainstem affecting vasomotor center - hypotension
- Sedation, dizziness, sleep disturbances, impotence, dry mouth, nasal congestion, postural hypotension
- Antihypertensive agent
Guanethidine
- Synaptic vesicle depletion and membrane depolarization
- Transported into adrenergic neurons via NET – reduces NE release
- Minimal adverse side effects – doesn’t cross BBB
- Orally effective hypertensive agent
Reserpine
- Synaptic vesicle depletion (pre-junctional)
- Depletes stores of NE in both CNS and PNS by blocking transport into vesicles
- Primarily in CNS (sedation, depression), increased GI motility (ulcers)
- Very potent, orally effective, long duration
- Cocaine
- DMI (desmethyl-imipramine)
- Amine I transport inhibitor
- Synaptic levels of NE rise and allow further sympathetic simulation
- Hyperactive sympathetic stimulation
- Hemostasis during surgery
Tyramine
- NE releasing agent
- Increases NE release into synapse – increased sympathetic effects
- Potentially dangerous for individuals on MAO inhibitors (elevates arterial pressure)
- Vasopressor (shock or hypotension)
Pseudoephedrine
- NE releasing agent
- Increases NE release into synapse
- Nasal congestion
- Acetazolamide
- Dichlorphenamide
- Dorzolamide
- Carbonic anhydrase inhibitor
- Reduce HCO3 production (required for aqueous humor production)
- Decrease aqueous humor production – open angle glaucoma
Botulinum Toxin A
- Misc. ophthalmology
- Blocks ability of ACh vesicles to move to nerve terminal surface and fuse – leads to relaxation in skeletal muscle
- Blepharospasm (eyelid problem) and squinting (extraocular muscles)