Exam 2: Neuro Agents: Autonomic Flashcards
Central vs peripheral
central: brain & spinal cord
peripheral: autonomic & somatic
Somatic Motor System
Voluntary
Acts on Skeletal Muscles
Autonomic Nervous System
Involuntary
Controls or regulates the functions of the heart, respiratory system, smooth muscles, GI system and glands
symp vs parasymp
Sympathetic Nervous System
Fight or Flight
Also Called Adrenergic
Main neurotransmitters are Norepinephrine and Epinephrine
Parasympathetic Nervous System
Rest and Digest
Also called Cholinergic
Also called Muscarinic
Main neurotransmitter is Acetylcholine
adrenergic receptors
sympathetic
Respond to Norepinephrine and Epinephrine
Alpha 1, Alpha 2, Beta 1 and Beta 2
cholinergic or muscarinic receptors
parasympathetic
Respond to Acetylcholine
Nicotinic and Muscarinic (cholinergic) receptors
alpha 1 receptor
located in the blood vessels
vasoconstriction (^BP)
mydriasis (pupil dilate)
bladder & prostate contraction
alpha 2 receptor
located on postganglionic nerve endings
vasodilates (acts a balance to alpha 1 so that there isn’t too much vasoconstriction)
decrease GI tone & motility
beta 1 receptor
primarily located in the heart (“1 heart”), but also in kidney
increased heart contraction & rate
releases renin from the kidneys into the blood -> ^ BP
beta 2 receptor
primarily located in the lungs (“2 lungs”)
bronchodilation
relaxes uterus
increases blood glucose through glycogenolysis
agonist
provokes a response
Catecholamines
Adrenergic Agonists
(Epinephrine, Norepinephrine, Isoproterenol, Dopamine and Dobutamine)
Cannot be taken orally
Short half life
Do not cross the blood brain barrier
Noncatecholamines
Adrenergic Agonists
Ephedrine, Phenylephrine, and Albuterol
Half life is longer than the catecholamine group
Can be taken orally
Does cross the blood brain barrier
Alpha I Receptor Agonists
Used for vasoconstriction in blood vessels
Treatment of nasal congestion
Stops bleeding (nose bleeds)
Raises Blood pressure
adverse: HTN, reflex bradycardia, necrosis at IV
extravasation
vesicant got into tissue from IV puncture and necrotic tissue
Alpha 2 Receptor Agonists
Used to treat Hypertension
ADR: Be careful in Geriatric population
May lead to orthostatic hypotension
Beta 1 Receptor Agonists
Treatment of cardiac arrest caused by asystole
Treatment of heart failure
Treatment of shock
Increases heart rate, force of contraction and cardiac output
ADR: altered HR/rhythm, angina
Beta 2 Receptor Agonists
Treatment of Asthma
Promotes bronchodilation
Treatment of Preterm Labor
Relaxes uterine smooth muscles
ADR: hyperglycemia, tremor
Epinephrine
adrenergic agonist
Alpha 1 - vasoconstrict (BP)
Beta 1 - heart contractility (HR)
Beta 2 - bronchodilation & ^BGL
catacholamine, so no PO
ADR: HTN, angina, necrosis from extravasation, ^BGL, dysrythmias
Isoproterenol Hydrochloride (Isuprel)
adrenergic agonist
Activates Beta 1 and Beta 2
Used for Bronchospasms with anesthesia
Used for Cardiovascular Disorders
AV heart block, cardiac arrest and increase cardiac output
ADR - tachydysrhythmias, angina, ^BGL
Clonidine (Catapres)
adrenergic agonist
Stimulates Alpha 2 receptors (vasodilate, dec. BP)
Also used for ADHD, management of cancer pain and neuropathic pain
Albuterol
adrenergic agonist
Primarily Beta 2, Minimal Beta 1
(bronchodilation and uterine relaxation)
Noncatecholamine
dopamine
adrenergic agonist
Catecholamine
Alpha 1, Beta 1 and Dopamine receptors
Used to treat:
Shock, HF, Acute Renal Failure
Dobutamine
adrenergic agonist
Causes selective activation of beta 1 receptors
The only indication is for treatment of HF
antagonist
blocks the typical response
Alpha 1 receptor antagonists
they block vasoconstriction, so vasodilation
Treat: HTN ,
Peripheral Vascular Disease (Raynaud’s Disease)
Benign Prostatic Hyperplasia -> decreases contraction in smooth muscle in bladder neck
can also use to reverse toxicity from an Alpha 1 agonist overdose (think about IV extravasation)
ADR: orthostatic hypotension, reflex tachycardia, nasal congestion
-zosins
adrenergic antagonist
Alpha 1 blockers
Prazosin (Minipress)
Terazosin (Hytrin)
dilation of arterioles and veins
HTN and BPH
ADR: orthostatic hypotension
Phentolamine
adrenergic antagonist
Blocks Alpha 1 and Alpha 2
Used to prevent tissue necrosis following extravasation of drugs that produce alpha 1 vasoconstriction
Beta blockers
adrenergic antagonists blocking beta receptors
end in “-lol”
decrease contractility and HR and velocity of conduction (AV node)
treats: angina, HTN (reduces PVR), dysrhythmias, MI, hyperthyroidism, migraine, stage fright(?)
ADR: bradycardia, reduced CO, bronchoconstriction, low BGL (only diabetics),
Metropolol (Lopressor) & Atenolol (Tenormin)
adrenergic antagonists
Selective Beta 1 Blockers
drug of choice for patients with lung issues (no bronchoconstriction) or DM (BGL)
Propranolol Hydrochloride (Inderal)
adrenergic antagonists
Nonselective for Beta 1 and Beta 2 (not for obstructive lung disease or DM)
Treats: angina, cardiac dysrhythmias, hypertension, and MI
Cholinergic agonists
Stimulate the Bladder
Stimulate the GI Tone
Constrict the Pupils
Treatment of Alzheimer’s and Myasthenia Gravis
Decrease HR & BP, increase secretions
Bethanechol (Urecholine)
Prototype Muscarinic Agonist
Cholinergic agent that elicits all of the parasympathetic responses (muscarinic receptor activation)
treats: urinary retention,
GERD (off-label)
ADR
With oral dosing, side effects are rare but could have full range of parasympathomimetic responses
Acetylcholinesterase
An enzyme that stops the action of acetylcholine
Cholinesterase Inhibitors
Inhibit Acetylcholinesterase
Thus, acetylcholine levels become elevated
Considered a “parasympathomimetic” agent
or a cholinergic agent
-stigmine
cholinergic agonists (AChE Inhibitors)
cholinergic effects
Neostigmine (Prostigmin)
Short acting, 2- 4 hours
Administered IM, IV or SubQ
(ion, poorly crosses membranes)
Physostigmine (Antilirium)
Similar to Neostigmine but PO
Treats: Myasthenia Gravis, toxicity of atropine and other anticholinergic (antimuscarinic) agents
Causes acetylcholine to build up at muscarinic junctions
Cholinergic Crisis
Overdose of Cholinesterase Inhibitors
Life threatening
Atropine Sulfate is the antidote
“SLUDGE”
S: Salivation
L: Lacrimation
U: Urination (relaxation of internal bladder sphincter)
D: Diarrhea
G: GI distress
E: Emesis
myasthenia gravis
Autoimmune Neuromuscular disorder
Antibodies are produced that attack Nicotinic Receptors
have to be dosed on time, before meals or otherwise could enter respiratory distress
anticholinergic
inhibits the action of acetylcholine
Increase in the pulse rate
Decrease in GI motility
Relaxation of the bronchi
Decrease in salivation
Dilation of the pupils
ADR: tachycardia, urinary retention, dry mucous memb, blurred vision, increase in intraocular pressure (glaucoma contraind.), constipation
atropine
anticholinergic agent
Preop med to decrease salivary secretions and maintain heart rate
Increase heart rate when bradycardia is present
Dilate pupils for eye exams/eye surgery
Antidote for cholinergic overdose
Exposure to a nerve agent in a Bioterrorism attack
Oxybutynin (Ditropan)
anticholinergic agent
Urinary Tract Antispasmodic
Treats an overactive bladder
Used for Incontinence
Scopolamine
anticholinergic agent
Motion sickness and eye examinations
Ipratropium (Atrovent)
anticholinergic agent
Used for asthma, COPD and rhinitis
Administered by inhaler
Dicyclomine (Bentyl)
anticholinergic agent
Used for irritable bowel syndrome
