Adrenergic Agonists and Adrenergic Blockers Flashcards
NERVOUS SYSTEM
Central- brain and spinal cord
Peripheral- outside the brain and spinal cord
Autonomic (visceral) involuntary,
acts on smooth muscles and organs
Somatic (voluntary)
innervates skeletal muscles
AUTONOMIC NERVOUS SYSTEM
Sympathetic Adrenergic Neurotransmitter: Norepinephrine Epinephrine Dopamine Fight & Flight
Parasympathetic Cholinergic Neurotransmitter Acetylcholine Rest & Digest
Sympathetic/Adrenergic Response
notes
Missing (GU) bladder and uterus, skin, hypercoagulability
Stimulation of sympathetic nervous system or use of adrenergic drugs can cause (Sympathetic responses):
Mydriasis, bronchodilation
↑ heart rate; peripheral vasoconstriction (HTN)
relaxation of GI tract, bladder, and uterus (no BM, voiding, or babies while running from the bear)
decrease secretions in the lungs, saliva, GI tract
shunting of blood from GI, GU, & skin
Glycogenolysis and peripheral insulin resistance 🡺 hyperglycemia (in diabetics)
Sympathetic/Adrenergic Response
eyes: pupils dilate
heart: increased hr
kidneys:
release of epinephrine by adrenal gland
SHUNTING
increase coagulability
increase BP
bladder rectum: no BM of voiding or babies while running from the bear
ovaries:
no babies
GI: slowdown of digestive process
lungs: relaxation of bronchial tree
pancreas: mobilization of glucose
skin: hair stands up
fight and flight
Negative Feedback vs. Drugs
NEGATIVE FEEDBACK
(natural process)
Fight or flight stimuli =>
release of catecholamines
Activities adrenergic receptors
α1, β1, β2
High level of catecholamines activating
α2 => stops adrenergic system
Rest and digest stimuli =>
release of acetylcholine
Activates muscarinic receptors
Negative Feedback vs. Drugs
DRUGS
Adrenergic agonist BEAR Adrenergic antagonist CHICKEN Cholinergic (See next set of slide) CHICKEN Anticholinergic (See next set of slide) BEAR
BEAR
Bear adrenergic adrenergic agonist sympathomimetic anticholinergic
CHICKEN
Sleepy Chicken adrenergic antagonist adrenergic blockers sympatholytic cholinergic
Adrenergic Receptors
ALPHA 1
BLOOD VESSELS
EYE
BLADDER
PROSTATE
peripheral vasoconstriction–> increased BP
mydriasis
bladder sphincter/ prostate contraction and
detrusor muscle relaxation => urinary retention
Increased BP not necessarily HTN Urinary retention (bladder) v fluid retention (kidneys)
Adrenergic Receptors
ALPHA 2
inhibits norepinephrine release
promotes vasodilation–> decreased BP
miosis
Adrenergic Receptors
BETA 1
HEART
BLOOD VESSELS
increased force of contraction and HR –> increased:
HR
CO
Adrenergic Receptors
BETA 2
LUNG
bronchodilation
Classification of Adrenergic Agonists(Sympathomimetics)
SELECTIVE
NONSELECTIVE
SELECTIVE
works on specific receptor alpha 1 alpha 2 beta 1 beta 2
albuterol = selective beta 2 agonist
open airways and helps asthma and copd
at higher doses becomes nonselective and stimulating beta-1 causing tachycardia
NONSELECTIVE
effects different receptors at the same time, activates alpha-1, beta 1&2
increases BP
increases HR
open airway
Epinephrine IM:
for allergic reaction
Epinephrine IV:
for cardiac arrest
severe hypotension (shock_
epinephrine
α1, β1,β2
Vasoconstriction, ↑ HR, bronchodilation
Shock
cardiac arrest
ephedrine (Ephedrine) IV is used to treat low BP post anesthesia
guanfacine
guanfacine (Tenex) alpha2 agonist for ADHD vs. guaifenesin (Mucinex) cough suppressant
epinephrine
selective or nonselective
Nonselective
epinephrine
INDICATION
IM/SubQ: Allergic reactions (anaphylaxis)
IV: Cardiogenic shock (Cardiac arrest)
Aerosol: Airway obstruction (bronchospasm)
epinephrine
SIDE EFFECTS
High risk for extravasation
antidote: phentolamine mesylate
epinephrine
SIDE EFFECTS
Hypertension
Pulmonary edema, Dyspnea
Tachycardia
Dysrhythmias/ Palpitations
worsening prostate disease (BPH)
Urinary retention
If it crosses BBB (large dose)
Tremors, restlessness, dizziness, fall
Mydriasis
worsening glaucoma, photophobia
Hypercoagulability
DVT, PE, CVA, MI
Lower GI motility/secretions
poor absorption, N/V, constipation, xerostomia, hypoactive bowel sounds
Blood shunting
Acute kidney injury, ischemic bowel, cold skin
Glycogenolysis
Hyperglycemia particularly in DM
DVT: deep vein thrombosis (blood clots in venous system that may circulate to the lungs (PE)
PE: pulmonary embolism (blood clots in the lungs
CVA: cerebrovascular accident (stroke)
MI: myocardial infarction (reduced or stopped coronary circulation = heart attack)
RF: renal failure (abnormal labs: high BUN, creatinine, low GFR, oliguria, uremia)
Xerostomia: dry mouth
Adrenergic BlockersAdrenergic Antagonists(Sympatholytic)
Adrenergic Blockers at Receptorseffects & side-effects
effects & side-effects
Alpha 1 blocker
Beta 1 blocker
Alpha 1 blocker
decreased BP
orthastatic hypotension
reflex tachycardia
relax bladder neck and prostate
miosis
priaprism
low ejaculation and anorgasmia
Contractility: force of contraction
HR: heart rate
Priapism: extended time of erection resulting in tissue death
Beta 1 blocker
decreases contractility - negative intrope
decreases pulse rate or HR - negative chronotrope
inotrope: conductivity of electrical signal (action potential)
chronotrope: HR
