Adrenergic Drugs

Question 1

Epinephrine Uses

Answer 1

Anyphylactic shock, asthmatic attacks, cardiac arrest, local anesthetics

Question 2

Norepinephrine Uses

Answer 2

Tx shock bc it incrases vascular resistance and increases BP

*dopa is better bc it doesn’t dec blood flow to the kidney

Question 3

Dopamine Uses

Answer 3

Tx severe CHF, cardiogenic and septic shock, management of shock
(Based on doses dopamine activates D1 > β1 > α1)

Question 4

Fenoldopam

Answer 4

Selective D1 agonist

Use: tx HTN

Question 5

Isoproterenol

Answer 5

β1 and β2-agonist
Effects: bronchodilator (β2), increased HR (β1), decreases peripheral resistance by dilating skeletal m arterioles (β2)
Use: in ED so stimulate HR in pt w/ bradycardia or heart block

Question 6

Dobutamine

Answer 6

Selective β1-agonist
MOA: potent inotrope w/ mild chronotropic effects
Effects: mild vasodilation, increases myocardial O2 consumption
Use: acute heart failure, cardiogenic shock
*given for stress echo bc it increases cardiac O2 consumption

Question 7

Albuterol and Terbutaline

Answer 7

Short-acting β2-agonists

Use: asthma

Question 8

Salmeterol and Formoterol

Answer 8

Long-acting β2-agonist (12h)
Use: not suitable for prompt relief of breakthrough bronchospasm attacks (prophylaxis)
SE: tremor, restlessness, anxiety, tachycardia, apprehension

Question 9

Phenylephrine

Answer 9

Selective α1-agonist
Effects: vasoconstriction
Use: nasal decongestant, mydriatic, increase BP in hypotension resulting form vasodilation in septic shock or anesthesia, terminates supraventricular tachycardia

Question 10

Clonidine

Answer 10

Partial α2-agonist (central receptors)
Effects: reduces sympathetic outflow, reducing BP
SE: lethargy, sedation, xerostomia

Question 11

Methyldopa

Answer 11

α2-agonist
MOA: converted to α-methylNE which activates central α2 receptors
Use: decrease BP, drug of choice for tx of HTN during pregnancy
SE: sedation, impaired concentration, xerostomia

Question 12

Brimonidine

Answer 12

Selective α2-agonist
Effects: reduces aqueous humor production and increases outflow
Use: decrease IOP in glaucoma

Question 13

Amphetamine

Answer 13

Target: α1 on vasculature and β on heart
MOA: central stimulatory action

Question 14

Methylphenidate

Answer 14

Chem: analogue of amphetamine
Use: ADHD in children

Question 15

Tyramine

Answer 15

Found in fermented foods (ripe cheese and chianti wine)
MOA: oxidized by MAO
Effects: precipitates vasopressor episodes if pt is taking MAOI

Question 16

Cocaine

Answer 16

MOA: blocks reuptake of monoamines in cleft
Effects: potentiation and prolongation of central and peripheral actions

Question 17

Atomoxetine

Answer 17

MOA: selective inhibitor of NE reuptake transporter
Use: ADHD

Question 18

Modafinil

Answer 18

Chem: psychostimulant
MOA: inhibits NE and dopa transporters
Effects: increases concentration of NE/dopa/serotonin/Glu in synapse and decreases GABA levels
Use: narcolepsy

Question 19

Ephedrine

Answer 19

Chem: has CNS effects
Target α and β, releasing NE from nerve endings
MOA: long duration
Effects: increases BP, bronchodilation, increases alertness, decreases fatigue
Uses: pressor agent during spinal anesthesia when hypotension occurs frequently

Question 20

Pseudoephedrine

Answer 20

Chem: ephedrine enantiomer
Use: otc as decongestant

Question 21

Phenoxybenzamine

Answer 21

Irreversible α-antagonist

Use: pheochromocytoma prior to surgery, or chronic management of pheochromocytoma

Question 22

Phentolamine

Answer 22

Reversible α1 and α2 antagonist
Use: pheochromocytoma tx during surgery, blocking test to dx pheo, prevention of dermal necrosis after extravasation of NE, HTN crisis d/t stimulant OD, tx cocaine induced coronary syndrome, HTN crisis d/t Clonidine withdrawal or sympathomimetic amines

Question 23

Prazosin

Answer 23

Selective α1-antagonist

Use: tx HTN

Question 24

Terazosin and Doxazosin

Answer 24

α1-antagonists w/ longer t1/2 than Prazosin

Use: tx HTN and BPH

Question 25

Tamsulosin

Answer 25

Selective α1A receptor antagonist Use: BPH (little effect on PB, less likely to cause orthostatic hypotension)

Question 26

Yohimbine

Answer 26

α2-antagonist | Use: tx ED (in the past but replaced by phosphodiesterase type 5 inhibitors)

Question 27

Propranolol / Nadolol

Answer 27

β-antagonist

Question 28

Atenolol / Metoprolol

Answer 28

Selective β1-antagonist Indication: HTN pt w/ impaired pulmonary fxn, DM HTN pt's who are receiving insulin or oral hypoglycemic agents USE: HTN, angina pectoris, MI

Question 29

Labetalol

Answer 29

α1 and β-antagonist

Question 29

Timolol

Answer 29

Non-selective β-antagonist | Use: decrease IOP in glaucoma

Question 31

Labetalol

Answer 31

Competitive α1 and β-antagonist (potency = β > α) | Use: HTN

Question 32

Carvedilol

Answer 32

Competitive α1 and β-antagonist Use: HTN and CHF *has antioxidant properties

Question 33

Pindolol

Answer 33

Partial agonist w/ intrinsic sympathomimetic activity (ISA)

Question 34

α-methyltyrosine (Metyrosine)

Answer 34

Competitive inhibitor of Tyrosine Hydroxylase | Use: management of malignant pheo or pre-op prep for pheo resection

Question 35

Reserpine

Answer 35

Irreversibly blocks VMAT MOA: vesicles cannot store NE and dopa Effects: gradual decrease in BP and slowing of cardiac rate Use: tx HTN (in the past)

Question 36

Tetrabenazine

Answer 36

Reversible inhibitor of VMAT MOA: presynaptic depletion of catecholamines Indicated: tx of chorea assoc. w/ Huntington's Dz

Question 37

Epinephrine Cardio effects w/ high dose

Answer 37

β1 predominates so increased ventricular contraction, increased HR, and additionally some vasoconstriction by the α1 receptors

Question 38

Epinephrine Cardio effects w/ low dose

Answer 38

β2 predominates so there is drop in diastolic pressure d/t decrease of peripheral resistance controlled by β2 receptors then HR increases d/t β1

Question 39

Epinephrine Metabolic Effects

Answer 39

``` Increase glycogenolysis in liver (β2) Increase lypolysis (β1 and β2) ```

Question 40

NE w/ pre-tx of Atropine

Answer 40

Causes tachycardia when NE is given after Atropine

Question 41

Norepinephrine

Answer 41

Potent agonist of α1, α2, β1 (little effect on β2) Effects: vasoconstriction (α1), increase BP, baroreceptor reflex initiated d/t incrase in BP inducing rise in vagal activity = bradycardia

Question 42

Dopamine @ Low Infusion Rate

Answer 42

Activates D1 receptors Target: renal and coronary vessels Effects: vasodilation in coronary arteries, increase GFR, increase renal blood flow, increase in Na+ excretion

Question 43

Dopamine @ Intermediate Infusion Rate

Answer 43

Activates β1 receptors in heart increasing CO so inc SBP and increased MAP *(preservation of flow in heart and kidneys)

Question 44

Dopamine @ High Infusion Rate

Answer 44

Activates vascular α1 receptors causing vasoconstriction and a rise in BP to maintain BP in shock

Question 45

Contraindications of β2 blockers?

Answer 45

Asthmatics, vasospastic dz (raynaud or Prinzmental angina), and DM pt's