Exam 6 - Adrenergic Agonists & Antagonists Flashcards

1
Q

Characteristics of adrenergic agonists

A
  • Derivatives of B-phenylethylamine

- stimulate fight/flight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Catecholamines

A
  • 2 OH groups on ring
  • potent at B receptors
  • rapid inactivation by MAO/COMT
  • cannot give orally (too much COMT/MAO in gut)
  • do not enter CNS…too polar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Noncatecholamines

A
  • only 1 or no OH groups
  • longer duration of action
    • only MAO breaks it down…not very well
  • greater access to CNS….less polar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Substitutions on amine Nitrogen

A
  • more subs….more affinity for B receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Epinephrine

A
  • Adrenalin
  • endogenous neurotransmitter/hormone
  • released by adrenal medulla (80%….NE 20%)
  • BOTH alpha and beta
  • Increases HR/contractility/renin/CO
  • constricts skin/viscera vessels
  • dilates liver/skeletal muscle vessels
  • high dose = constrict (alpha)…low dose = dilate (B2)
  • HR up / systolic up…diastolic down / PVR down
  • bronchodilation / allergy inhibition
  • hyperglycemia (increase glucagon / decrease insulin..alpha)
  • Lipolysis (B3)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Epinephrine therapeutic uses

A
  • Cardiac arrest
  • Anaphylactic shock
  • Acute asthma attack / bronchospasm
  • With local anesthetics….to keep local
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Epi CPR dose

A

1 mg IV/IO every 3-5 min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Epi bradycardia dose

A

2-10 ug/min IV to effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Epinephrine pharmacokinetics

A
  • Rapid onset, short duration
    • due to MAO/COMT….is a catecholamine
  • IM/IV/IO/SQ/inhalation/endotracheal….NOT orally
  • excreted by kidney
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Norepinephrine

A
  • Levophed (leave em dead)
  • endogenous neurotransmitter of adrenergic nerves
  • Alpha and B1
  • Intense vasoconstriction
  • Increase contractility BUT barrorecpetor reflex….so HR down
  • HR down / systolic up…diastolic up / PVR up
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

NE therapeutic uses

A
  • Vasodilatory shock

- Hypotension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

NE dose

A

0.5-12 ug/min to titrated to effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

NE pharmacokinetics

A
  • lasts 1-2 minutes
  • rapidly metabolized by MAO/COMT
  • excreted via kidney
  • IV ONLY…extravasation cause necrosis…no peripheral veins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Dopamine

A
  • endogenous precursor to NE…neurotransmitter and hormone
  • CNS/adrenal medulla
  • D (low= 1-2 ug/kg/min) > B (medium= 2-10) > alpha (high= >10)
  • HR up / contractility up
  • contracts at HIGH doses
  • dilates renal/splanchnic arteries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Dopamine therapeutic uses

A
  • MAIN drug for cardiogenic/septic shock
  • Renal failure…increases renal flow
  • Hypotension/heart failure…especially if with renal failure
    • NE will decrease renal flow even more
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Dobutamine

A
  • Dobutrex
  • synthetic, direct catecholamine
  • B1
  • Increases CO/HR ( < dopamine)/Contractility ( >dopamine)
  • NO PVR effect
  • Less increase in O2 consumption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Dobutamine therapeutic uses

A
  • Increase CO in acute heart failure

- short term “failure to wean” drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Isoproterenol

A
  • Isuprel
  • synthetic catecholamine
  • Nonselective B1 and B2
  • Increase contractility/HR
  • potent vaso/bronchodilator
  • Up HR / zero-little up systolic…down diastolic / down PVR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Isoproterenol therapeutic uses

A
  • Second choice for cardiac emergency
  • bronchospasms during anesthesia
  • cardiac stimulant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Phenylephrine

A
  • Neo-Synephrine
  • synthetic Alpha 1
  • lasts 20 min (longer than epi/NE)
  • constriction
  • Up systolic….up diastolic
  • Drops HR….due to reflex bradycardia…like NE
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Phenylephrine theraputic uses

A
  • Hypotension
  • Tachycardia
  • Nasal decongestant if topical/oral
  • VERY common to increase SVR and MAP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Neo dosing

A
  • Start with test dose (50-100 ug/ml)
  • LD = 50-500 ug
  • IV = 10-15 in 250 ml fluid (40-60 ug/ml)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Indirect adrenergic agonists

A
  • increase endogenous levels of Epi/NE
    • cause release / inhibit reuptake / inhibit degradation
  • Amphetamine / Tyramine / Cocaine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Amphetamine

A
  • reverse NE reuptake channels on presynaptic terminal

- more release of NE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Cocaine

A
  • binds and blocks reuptake NE receptors
26
Q

Mixed action adrenergic agonists

A

Ephedrine (if no epi) > Pseudoephedrine (decongestant)

  • release stored NE…AND
  • directly stimulate alpha/beta
  • Like epi…less potent….longer duration
  • vasoconstriction / cardiac stimulation / Up systolic AND diastolic
  • Mild CNS
27
Q

Side effects of adrenergic agonists

A
  • arrhythmia
  • headache
  • hyperactivity
  • insomnia
  • nausea
  • tremors
28
Q

Dopaminergic agonists

A
  • Levodopa
  • goes into CNS…turns into dopamine…stays in CNS
  • useful for Parkinson’s
29
Q

Direct Adrenergic Agonist Drugs

A
  • Epinephrine (Adrenalin)
  • NE (Levophed)
  • Dopamine
  • Dobutamine (Dobutrex)
  • Isoproterenol (Isuprel)
  • Phenylephrine (Neo-Synephrine)
30
Q

Indirect Adrenergic Agonist Drugs

A
  • Amphetamine
  • Tyramine
  • Cocaine
31
Q

Mixed Action Adrenergic Drugs

A
  • Ephedrine

- Pseudoephedrine

32
Q

Dopaminergic Agonist Drugs

A
  • Levodopa
33
Q

Adrenergic Antagonists

A
  • no need to use on B2
  • sympatholytics
  • alpha and beta blockers
34
Q

Alpha blockers

A
  • vasodilates
  • severely drops BP
  • causes reflex tachycardia
35
Q

Alpha 1 receptors

A
  • increase vascular tone
  • smooth muscle vasculature
  • on effector organ
  • constricts when stimulated
36
Q

Alpha 2 receptors

A
  • presynaptic
  • control release of NE
  • inhibitory autoreceptors
  • stimulation blocks NE release
37
Q

Phenoxybenzamine

A
  • Dibenzyline
  • Nonselective alpha blocker
  • Noncompetitive….covalently bonds
  • irreversible…long lasting
  • vasodilates / reflex tachycardia
  • blocks inhibitory alpha2 receptors on heart…more NE…up CO

Uses:

  • Pheochromocytoma: too much adrenaline from adrenal gland
  • DONT use for hypertension…it increases CO
38
Q

Phentolamine

A
  • Regitine
  • Nonselective alpha blocker
  • competitive
  • short lasting…4 hours

Uses:

  • short term pheochromocytoma
  • locally to prevent dermal necrosis…NE extravasation
  • Epi reversal… blocks alpha effects of Epi
39
Q

Nonspecific alpha blocker side effects

A
  • orthostatic hypotension
  • tachycardia
  • dizzy/headache
  • sexual dysfunction
40
Q

Selective Alpha 1 blockers

A
  • Prazosin (minipress)
  • Terazosin (Hytrin)
  • Doxazosin (Cardura)
  • used for hypertension w/ other things…also BPH
  • competitive
  • decrease PVR and lower BP
  • minimal changes to CO (no B)
  • first dose may cause orthostatic hypotension
41
Q

Selective alpha 2 blockers

A
  • Yohimbine
  • competitive
  • more sympathetic to periphery
  • treats impotence/aphrodisiac
42
Q

Beta blockers

A
  • think -olol
  • competitive
  • widely used
  • patient specific dosing (usually judge via HR)
43
Q

Beta blocker uses

A
  • hypertension
  • angina
  • arrhythmias
  • MI
  • heart failure
  • hyperthyroidism
  • glaucoma
  • migraine prophylaxis
44
Q

Propranolol

A
  • Inderal
  • Gold standard
  • blocks B1 and B2 equally
  • down HR / contractility / CO / oxygen consumption
  • PVR up initially…but normal or decrease with long term use
    • due to reflex peripheral constriction
45
Q

Propranolol bronchial effects

A
  • constriction

- DON’T use for COPD

46
Q

Propranolol glucose effects

A
  • Hypoglycemia
  • decrease glucagon secretion
  • careful with diabetic patients
47
Q

Propranolol drug interactions

A
  • blocks isoproterenol (B agonist)
    • no cardiac stimulation (B1)
    • no drop in MAP and diastolic BP (B2)
  • blocks SOME Epi
    • leaves alpha 1 alone…. vasoconstriction action unimpaired
48
Q

Propranolol therapeutic uses

A
  • hypertension (drops work of heart and PVR over time)
  • angina (less O2 used)
  • MI (better recovery and preventative for future MI)
  • migraine (prophylactically)
  • hyperthyroidism
  • stage fright / anxiety
49
Q

Propranolol adverse effects

A
  • bronchoconstriction
  • arrhythmias (receptor upregulation / DO NOT stop abrupt)
  • sexual dysfunction
  • metabolic disturbance (high LDL / low HDL / more fat…B3)
  • CNS effects:
    • depression / dizzy / weak / tired / hallucination / STML
50
Q

Nadolol

A
  • Corgard
  • blocks B1 and B2 equal
  • nonselective
  • similar to propranolol but MORE potent
  • longer duration….12-24 hours
    Uses:
    -Hypertension
51
Q

Selective B1 blockers

A
  • can effect B2 with high dose…still careful w/ COPD
  • less bronchoconstriction at low dose

Uses:

  • lower BP in hypertension…especially w/ impaired pulmonary
  • increase exercise in angina
  • chronic angina therapy
  • chronic heart failure
    • Bisoprolol / Metoprolol (extd. release)
52
Q

Esmolol

A
  • Brevibloc
  • B1 blocker
  • very short half life
  • IV
  • used for BP or rhythm in surgery
53
Q

Selective B1 blocker w/ partial agonist activity

A
  • Acebutolol (Sectral)
  • ISA - Intrinsic sympathomimetic activity
    • weakly activates AND blocks from other potent binding
  • leads to decrease in cell activity…not total block
  • less effect on CO/HR but minimal lipid/carb disturbance

Uses:
- hypertension w/ bradycardia …drop in HR is less

54
Q

Nonselective B block w/ alpha-1 blocking actions

A
  • Labetalol (Trandate)
  • Carvedilol (Coreg)
  • peripheral dilation (block alpha 1)
  • reduce BP
    Uses:
  • Hypertensive emergency (IV)
  • Pregnancy hypertension
55
Q

Non Selective alpha blockers

A

“-amine”

  • Phenooxybenzamine (Dibenzyline)
  • Phentolamine (Regitine)
56
Q

Selective alpha 1 blockers

A

“-azosin”

  • Prazosin (Minipress)
  • Terazosin (Hytrin)
  • Doxazosin (Cardura)
57
Q

Selective alpha 2 blocker

A
  • Yohimbine
58
Q

Non Selective B blockers

A
  • Propranolol (Inderal)

- Nadolol (Corgard)

59
Q

Selective B1 Blockers

A
  • Esmolol (Brevibloc)
  • Atenolol (Tenormin)
  • Metoprolol (Lopressor)
  • Bisoprolol (Zebeta)
60
Q

Selective B1 blockers w/ partial agonist activity

A
  • Acebutolol (Sectral)
61
Q

Non Selective B Blockers w/ Alpha-1 block activity

A
  • Labetalol (Trandate)

- Carvedilol (Coreg)