Sympathomimetics

Question 1

a1 potency

Answer 1

epi>Ne»ISO

Question 2

A2 potency

Answer 2

Epi>NE»ISO

Question 3

B1 potency

Answer 3

Iso>Epi=NE

Question 4

B2 potency

Answer 4

Iso>Epi»NE

Question 5

Epinephrine Pharmocologcial effects

Answer 5

Increase HR
increased contractility
increased conduction velocity in the heart
increased oxygen consumption and work done by the heart

greater affinity for B2 so at low doses–>decreased BP, but at higher doses it binds to a1–>vasoconstriction

Question 6

Epi and coronary vessels

Answer 6

vasodilation B2

Question 7

epi and kidney, mucosa and skin

Answer 7

vasoconstriction a1

Question 8

epi and pulmonary vasculature

Answer 8

vasoconstriction a1

Question 9

Clinical uses for epi

Answer 9

1) Asthma: bronchodilation (B2) and vasoconstriction (a1)
2) anaphylactic shock: immediate SC injection: bronchodilation, decreased edema (VC), decreased histamine, alleviates Hypotension
3) cardiac resuscitation
4) topical hemostatic
5) Infiltration with local anesthetics (keeps them local)

Question 10

Epinephrine adverse effects

Answer 10

arrhythmias (esp when dosed with gas anesthetics)
cerebral hemorrhage
necrosis at injection site
CNS: fear , anxiety, HA

Question 11

epinephrine contraindications

Answer 11

HTN 
shock
hyperthyroidism (can increase arrhythmias) 
angina 
asthmatics with CVD

Question 12

NE pharmacology

Answer 12

a1 and B1 agonist (NO B2)
positive inotropic effects (B1), negative chronotropic effects (REFLEX)

vasoconstriction (a1)= always increased HR

Question 13

NE uses, s/e

Answer 13

IV to manage hypotension during spinal anesthesia
anxiety, slow forceful heartbeat, HA

same contraindications as Epi

Question 14

Dopamine pharmacology and function

Answer 14

B1 and D1 agonist, a1 at high concentrations
renal vasodilators

used for cardiogenic shock, increased CO and increases Kidney excretion

Question 15

Dobutamine

Answer 15

B1 selective agonist
positive inotropy and chronotropy = increased CO
used fro MI, CHF, cardiogenic shock

Question 16

Phenylephrine pharm

Answer 16

a1 agonist (non-catecholamine)= longer lasting and can be PO

Vasoconstriction
increased TPR, increased BP
Reflex bradycardia

Question 17

Phenylephrine clinical uses

Answer 17

1) Maintain BP in hypotensive states (spinal anesthesia)
2) paroxysmal atrial tachycardia (reflex brady)
3) nasal decongestant
4) Glaucoma
5) infiltration with anesthetics

Question 18

Albuterol

Answer 18

relatively selective B2 agonist (10x vs B1)
bronchodilation used for asthma

aerosolized decreases systemic effects (PO sometimes used)

desensitization may occur

Question 19

Salmeterol

Answer 19

long active selective B2 agonist
better for nighttime asthma or prophylaxis tx

Formoterol does same thing

Question 20

Tyramine

Answer 20

Displaces NE from nerve terminal
normally degraded by MAO in gut
found in high levels in foods, so pt on MAOI can get hypertensive crisis

reuptake also inhibited by cocaine

Question 21

Cocaine

Answer 21

competitively block the reuptake of NE into nerve terminal, NE levels in the synapse are higher for longer

also block tyramine uptake

Question 22

amphetamines

Answer 22

cause release of NE from adrenergic nerve endings ( indirect)
increase alertness, fatigue, mood, increased HR etc.

relatively hydrophobic and enter CNS

e.g. adderall

Question 23

Ephedrine

Answer 23

mixed acting agonist
Direct: B receptor agonist
Indirect: releases NE

not metabolized by COMT or MAO (long lasting)
CV: increased HR and VC
bronchodilation

used as a pressor, nasal decongestant