Sketchy Pharm: Autonomic Drugs Flashcards
(129 cards)
1
Q
Cholinomimetics:
What are cholinomimetics?
A
substances that mimic or modify the actions of acetylcholine, an essential neurotransmitter in the parasympathetic nervous system
2
Q
Cholinomimetics:
What are the subtypes of acetylcholine receptors?
A
Muscarinic receptors and nicotinic receptors.
3
Q
Cholinomimetics:
Where are nicotinic Ach receptors found?
A
On autonomic ganglia, skeletal muscle motor end plates (neural muscular junction), and the adrenal glands.
Act more as ion channels.
4
Q
Cholinomimetics:
What are the muscarinic Ach receptors?
A
M1, M2, and M3
5
Q
Cholinomimetics:
What are the signaling pathways for the muscarinic receptors?
A
G-Protein coupled:
M1, M2, and M3 are coupled to Gq, Gi, and Gq respectively.
6
Q
Cholinomimetics:
What do M1 and M3 receptors have in common?
A
Both are coupled to Gq proteins which activate the IP3-DAG cascade.
Leading to increased intracellular calcium.
7
Q
Cholinomimetics:
Where can you find M1 receptors?
A
Nerves and the CNS
8
Q
Cholinomimetics:
Where can you find M2 receptors?
A
Atria, SA, and AV node
9
Q
Cholinomimetics:
Where can you find M3 receptors?
A
Smooth muscles and glands.
10
Q
Cholinomimetics:
What occurs upon M3 receptor activation?
What in the case of atherosclerosis?
A
1)
Nitric oxide release in vascular smooth muscle cells
–>
Increased cGMP and vasodilation
2)
Atherosclerosis -> vascular epithelial damage -> direct muscarinic receptor activation -> vasoconstriction
11
Q
Cholinomimetics:
What is the MOA of Bethanechol?
A
Increases secretion and motor activity of the gut.
Beneficial for non-obstructive urinary retention and specific GI disorders; ie post-op ileus, neurogenic ileus, or congenital megacolon.
Stimulates detrusor muscle and relaxes the bladder sphincter.
12
Q
Cholinomimetics:
What is the MOA of Pilocarpine?
A
Increases salvation.
Useful in dry mouth in cases of Sjrogrens, radiation damage, or in glaucoma.
In glaucoma it contracts the ciliary body to allowing aqueous humor to flow better, relaxing the zonular fibers and have the lens form a more spherical shape.
13
Q
Cholinomimetics:
What is the MOA of carbachol?
A
Causes pupillary constriction.
Useful in acute angle-closure glaucoma.
It is both a muscarinic and nicotinic agonist.
14
Q
Cholinomimetics:
What is methacholine used for?
A
Induces wheezing symptoms useful in asthma diagnostic testing. It contracts bronchial smooth muscle which may exacerbate asthma or COPD, or peptic ulcers.
**This can occur with other
15
Q
Cholinomimetics:
What is the MOAH of Veranicline?
A
Partial agonist at nicotinic receptors.
Used in smoking cessation.
16
Q
Parasympathetic; Acetylcholinesterase inhibitors:
What is the pathophys of Myasthenia Gravis?
A
Antibodies against nicotinic ACh receptors at motor endplate
17
Q
Parasympathetic; Acetylcholinesterase inhibitors:
How does MG present?
A
Ptosis, diplopia, difficulty in swallowing, proximal limb weakness getting worse with use.
18
Q
Parasympathetic; Acetylcholinesterase inhibitors:
What is the longterm tx for MG?
A
Pyridostigmine
- Neostigmine is also used but not commonly
*Provides only symptoms
19
Q
Parasympathetic; Acetylcholinesterase inhibitors:
What agents can you use to block neuromuscular activity during surgery?
A
Nondepolarizing neuromuscular blocking agents
ie Vecuronium. tuocurarine, and cisatracurium
- competitively inhibit nicotinic ACh receptors at NMJ endplate
20
Q
Parasympathetic; Acetylcholinesterase inhibitors:
How can you reverse the effects of non depolarizing NM blocking agents ie post-op?
A
Acetocholinesterase inhibitors (e.g. neostigmine)
21
Q
Parasympathetic; Acetylcholinesterase inhibitors:
What is an example of a depolarizing neuromuscular blocking agent ?
A
Succinylcholine, it’s a nicotinic ACh receptor agonist.
22
Q
Parasympathetic; Acetylcholinesterase inhibitors:
What medication can you use to treat post-op urinary retention?
A
Neostigmine
- at muscarininc receptors
23
Q
Parasympathetic; Acetylcholinesterase inhibitors:
Which ACh-ase inhibitor is commonly used in the CNS?
A
Physostigmine, has peripheral AND central nervous system, use sparingly.
24
Q
Parasympathetic; Acetylcholinesterase inhibitors:
What is the tx for Atropine overdose?
A
Physostigmine
hint: “mad as a hatter, hot as a hare, blind as a bat”
25
Parasympathetic; Acetylcholinesterase inhibitors:
What flower is associated with atropine poisoning?
Belladonna flower, again treat with Physostigmine
"Deadly nightshade
Also Jimson weed- "Gardener's Mydriasis
26
Parasympathetic; Acetylcholinesterase inhibitors:
How will you remember Acetylchlinesterase inhibitor toxicity?
DUMBBELSS
- diarrhea
- urination
- miosis
- bronchospasm
- bradycardia
- lacrimation
- salivation
- sweating
27
Parasympathetic; Acetylcholinesterase inhibitors:
What is the effect of acetylcholinesterase inhibitor toxicity on nicotinic receptors?
Flaccid paralysis via over activation
28
Parasympathetic; Acetylcholinesterase inhibitors:
What is the cause of acute cholinergic toxicity?
Organophosphates found in pesticides and insecitides
ie Parathion, malathion, echothiophate
29
Parasympathetic; Acetylcholinesterase inhibitors:
What is the treatment for acute cholinergic toxicity?
Pralidoxime, regenerates ACh-ase at M and N receptors
Atropine is to reverse central, but as well as peripheral symtoms
30
Parasympathetic; Acetylcholinesterase inhibitors:
At what point in cholinergic toxicity is when Pralidoxime no longer works?
Aging
31
Parasympathetic; Acetylcholinesterase inhibitors:
What Acetylcholinesterase inhibitor is used in Alzheimer's disease?
Galantamine, Rivastigmine, and Donepezil.
- All penetrate the CNS to treat the cognitive symptoms
32
Parasympathetic; Acetylcholinesterase inhibitors:
Why can't neostigmine and pyridostigmine penetrate the CNS?
Contains a charged quaternary ammonium group
33
Parasympathetic; Muscarinic Antagonists:
Are muscarinic antagonists reversible or irreversible?
Reversible
34
Parasympathetic; Muscarinic Antagonists:
What are the effects of antimuscarinics?
Mydriasis (pupillary dilation)
Cycloplegia (inability to accommodate the lens for near vision because of weakened ciliary muscle contraction)
35
Parasympathetic; Muscarinic Antagonists:
What antimuscarinic is used to treat sea sickness?
How does it work?
Scopolamine
Cross BBB and inhibit M1 receptors
36
Parasympathetic; Muscarinic Antagonists:
What is the effect of antimuscarinics on the heart?
Blocks parasympathetic activation of M2 receptors on the SA and SV nodes.
Increases HR and AV conduction
ie: Atropine
37
Parasympathetic; Muscarinic Antagonists:
What antimuscarinics are used in cases like COPD?
Ipratropium and tiotropium
- M3 muscarinic antagonists, used as inhaled bronchodilators and decreases secretions
38
Parasympathetic; Muscarinic Antagonists:
What antimuscarinic agent is used in urinary incontinence post op or neurological incontinece?
Oxybutynin and Tolterodine
- M3 muscarinic antagonist to reduce involuntary voiding
39
Parasympathetic; Muscarinic Antagonists:
What disease are M1 receptors blocked using antimuscarinics?
Parkinsons Disease
ie Bentropine and Trihexyphenidyl
*Treats tremor and rigidity by blocking excess cholinergic activity
40
Parasympathetic; Muscarinic Antagonists:
Say a Pt is experiencing bradycardia, treat with antimuscarinics, now pt complains of right eye pain, what is occurring?
decreased outflow asquous humor -> acute angle closure glaucoma
41
Parasympathetic; Muscarinic Antagonists:
What can antimuscarinics cause if they cross the BBB and block M1 receptors?
Sedation, agitation, hallucination, amnesia coma
(especially in elderly)
"Mad as a hatter"
42
Parasympathetic; Muscarinic Antagonists:
Where are M2 receptors primarily located?
Myocardium and smooth muscle
43
Sympathetic: Sympathomimetics
What is the signaling pathway for each adrenergic receptors?
- Alpha 1 - Gq
- Alpha 2 - Gi
- Beta 1- Gs
- Beta 2- Gs
"QISS"/Kiss
44
Sympathetic: Sympathomimetics
What pathway does Gq stimulation cause?
Activated IP3-DAG pathway increases intracellular calcium in smooth muscles in vasculature and sphincters. Leading to vasoconstriction of both arteries and veins.
Increases MAP and venous return, helpful in hypovolemic and distributive shock.
45
Sympathetic: Sympathomimetics
What is the effect of alpha 1 agonism on the eyes?
Mydriases/pupillary dilation
46
Sympathetic: Sympathomimetics
What is the effect of alpha 1 agonism on the Genitourinary tract?
Causes urethral sphincter and prostatic smooth muscle contraction, leading to urinary retention
47
Sympathetic: Sympathomimetics
What does alpha 2 agonism do?
Centrally act to decrease sympathetic tone
48
Sympathetic: Sympathomimetics
Where do alpha 2 receptors prevent neurotransmitter release?
Presynaptically
49
Sympathetic: Sympathomimetics
Where are alpha 2 cell located?
Pancreatic Islet cells, agonism causes a decrease in insulin release.
50
Sympathetic: Sympathomimetics
What is alpha 2 agonism effects on fats?
Inhibition of lipolysis and release of fatty acids
51
Sympathetic: Sympathomimetics
What is the effect of alpha 2 receptors on the ciliary body?
Decreases aqueous humor production.
- Brimonidine, used in chronic open angle glaucoma
52
Sympathetic: Sympathomimetics
Where are beta 1 receptors found?
Cardiac myocytes, including SA and AV nodes
**Also Juxtoglomerular cells (increases renin release)
53
Sympathetic: Sympathomimetics
What is the effect of increased cAMP?
Increased intracellular calcium
54
Sympathetic: Sympathomimetics
How does Beta 1 stimulation increase heart rate?
Increase activation at the SA node.
55
Sympathetic: Sympathomimetics
What is the effect of Beta 2 receptor activation?
Relaxes smooth muscles ultimately causing bronchodilation
56
Sympathetic: Sympathomimetics
What is the effect of beta 2 receptor activation?
diastolic pressure drop
57
Sympathetic: Sympathomimetics
Where are Beta 2 receptors found?
Smooth muscle
Adipose tissue: activating fatty acid release and lipolysis
Liver: activated gluconeogenesis
Pancreas: activation of Islet cells to promote insulin release
58
Sympathetic: Sympathomimetics
What electrolyte abnormality is common in beta 2 activation?
Hypokalemia (think insulin)
59
Sympathetic: Sympathomimetics
What is the effect of beta 2 activation in the ciliary body?
Increases aqueous humor production
60
Sympathetic: Sympathomimetics
What is the effect of Phenylephrine?
Pure alpha 1 agonist
Treats nasal congestion, causes mydriasis by stimulating pupillary dilator muscle, used a pressor agent,
Increases systolic pressure via arteriolar constriction and increases diastolic BP via venous constriction. Increases MAP via increasing SVR.
*causes reflex bradycardia
61
Sympathetic: Sympathomimetics
What receptors are associated with Norepinephrine?
Alpha > beta 1 agonist
Primarily an alpha agonist
62
Sympathetic: Sympathomimetics
What receptor are associated with Dobutamine?
Beta 1 > beta 2 agonist
Primarily Beta 1
63
Sympathetic: Sympathomimetics
What is the effect of Dobutamine on pulse pressure?
Increases pulse pressure
64
Sympathetic: Sympathomimetics
What kind of shock is Dobutamine used for?
Cardiogenic shock
65
Sympathetic: Sympathomimetics
What medication can you use for a cardiac stress test if pt can't tolerate exercise?
Dobutamine
66
Sympathetic: Sympathomimetics
What receptors are associated with Isoproterenol?
Beta1=Beta2
67
Sympathetic: Sympathomimetics
What is Dobutamine's effect on Pulse pressure, MAP, and diastolic pressure?
- increase in PP from beta1 increase in contractility
- decrease in MAP from Beta2 decrease in SVR
- decrease in diastolic pressure from Beta2 arteriolar dilation
68
Sympathetic: Sympathomimetics
What is the effect of Beta 2 agonism on uterus?
Relaxes uterine smooth muscle
- ie Terbutaline prevents premature labor
69
Sympathetic: Sympathomimetics
How can you remember beta 2 agonistic medications in treating asthma?
"-rol" suffix
- albuterol, formoterol, salmeterol
70
Sympathetic: Sympathomimetics
What receptors are associated with Epinephrine?
Describe the dose dependency:
Beta > alpha
At low doses, Epi has predominantly beta agonism, so decrease in diastolic pressure via vasodilation and decrease SVR (beta 2)
Also increases HR and contractility via Beta 1 effects
At higher doses, alpha effects predominate
71
Sympathetic: Sympathomimetics
Does epinephrine cause bronchodilation or bronchocontriction?
Brochodilation
72
Sympathetic: Sympathomimetics
Describe the different effects of adrenergic receptors on a graph:
73
Sympathetic: Indirect Sympathomimetics
What is the amino acid precursor to all catecholamines?
Tyrosine
74
Sympathetic: Indirect Sympathomimetics
How does Metyrosine work?
It's a tyrosine analog that prevents the conversion of tyrosine to L-DOPA
75
Sympathetic: Indirect Sympathomimetics
What enzyme converts dopamine to NE?
Dopamine-Beta-Hydroxylase
76
Sympathetic: Indirect Sympathomimetics
What assists in the reuptake of NE and Dopamine?
NET and DAT
*targets of many recreational drugs ie cocaine
77
Sympathetic: Indirect Sympathomimetics
What can cocaine cause?
Agitation, pupillary dilation, HTN, and tachycardia
*Look for mucosal atrophy or nasal septal perforation, this is due to vasoconstriction.
78
Sympathetic: Indirect Sympathomimetics
What are the effects of cocaine on the heart?
Coronary vasospasm leading to angina and myocardial ischemia.
79
Sympathetic: Indirect Sympathomimetics
What drug class is to be avoided in a pt suspected of cocaine intoxication?
Beta blockers
- can lead to unopposed alpha-1 stimulation and extreme hypertension
80
Sympathetic: Indirect Sympathomimetics
What agent can treat attention deficit and hyperactivity disorder (ADHD)?
Atomoxetine, it's a NET inhibitor
81
Sympathetic: Indirect Sympathomimetics
How are Catecholamines transported back into the presynaptic vesicle?
What inhibits this?
VMAT- vesicular monoamine transporter
* Reserpine inhibits VMAT, depleting neurotransmitter stores
82
Sympathetic: Indirect Sympathomimetics
What are amphetamines effects on catecholamines?
Displace NE and Dopamine into the synapse
Treats ADHD ie methylphenidate
83
Sympathetic: Indirect Sympathomimetics
Which amphetamine derivative treats narcolepsy?
Modafinil, it's a stimulant
84
Sympathetic: Indirect Sympathomimetics
What is a common side effect to amphetamines, methylphenidate, and modafinil?
all suppress appetite
85
Sympathetic: Indirect Sympathomimetics
Which signaling pathways are associated with D1 and D2?
Gs and Gi respectively
86
Sympathetic: Indirect Sympathomimetics
What is the effect of low dose dopamine on RBF?
Low dose stimulates D1 receptors to INCREASE RBF.
87
Sympathetic: Indirect Sympathomimetics
What is the effect of medium dose dopamine?
Activates Beta-1 receptors (cardiac activation)
88
Sympathetic: Indirect Sympathomimetics
What is the effect of high dose dopamine?
activates alpha-1 receptors (pressor effects)
89
Sympathetic: Indirect Sympathomimetics
Where are D2 receptors found?
CNS
90
Sympathetic: Alpha Drugs:
How does Clonidine act?
Alpha 2 agonist
91
Sympathetic: Alpha Drugs:
How do alpha 2 agonists effect the CNS?
Inhibit sympathetic tone reducing blood pressure
"A sympatholytic to treat high blood pressure"
92
Sympathetic: Alpha Drugs:
What medication is used to treat hypertensive urgency?
Clonidine- Alpha 2 agonist
93
Sympathetic: Alpha Drugs:
What can you give to a pt with refractory ADHD (typical treatment is not working)?
Clonidine- Alpha 2 agonist
94
Sympathetic: Alpha Drugs:
What medication is first line for chronic tics or Tourette's syndrome?
Clonidine- Alpha 2 agonist
95
Sympathetic: Alpha Drugs:
What alpha 2 agonist can be used in a pregnant pt with HTN?
alpha-methyldopa
96
Sympathetic: Alpha Drugs:
What is the side effect to alpha-methyldopa?
Lupus-like syndrome
97
Sympathetic: Alpha Drugs:
What centrally acting alpha 2 agonist is used as a muscle relaxant?
Tizanidine
98
Sympathetic: Alpha Drugs:
What is the MOA of Phentolamine?
Reversible alpha 1 and alpha 2 antagonist
99
Sympathetic: Alpha Drugs:
What medication binds irreversibly to alpha 1 and 2?
Phenoxybanzamine
100
What drug class can be used to treat cocaine toxicity?
Alpha antagonists like phentolamine
101
Sympathetic: Alpha Drugs:
What sympathomimetic is contained in wine and aged cheese?
Tyramine, metabolized by monoamine oxidase-A
If a patient is on a MAO-A inhibitor, Tyramine build up and causes a hypertensive crisis. Treat with Phentolamine (alpha antagonist)
MOA-A also metabolizes Epi and NE
102
Sympathetic: Alpha Drugs:
What enzyme metabolizes dopamine?
MOA-B
103
What is used prophylactically for pre-op to excise a pheochromocytoma?
Phentolamine- controls BP
104
Sympathetic: Alpha Drugs:
What is a side effect of alpha 1 antagonism?
orthostatic hypotension, also reflex tachycardia
105
Sympathetic: Alpha Drugs:
How can you distinguish selective alpha 1 antagonists?
"-osin" suffix
- eg prazosin, terazosin, doxazosin, tamsulosin
106
Sympathetic: Alpha Drugs:
What medication can you give to treat symptoms of BPH?
Terazosin
- selective Alpha 1 blocker, relaxes smooth muscle in the urethra and prostate
107
Sympathetic: Alpha Drugs:
What selective alpha 1 blocker can be used to treat PTSD?
Prazosin
108
Sympathetic: Alpha Drugs:
What medication is used as an atypical antidepressant with antagonists effects at alpha 2 receptors?
Mirtazipine
109
Sympathetic: Beta Blockers:
What is the danger in using beta blockers in a patient already taking negative inotropic agents?
Can cause or exacerbate heart block due to excessive suppression of AV node conduction
110
Sympathetic: Beta Blockers:
Can you use beta blocker to treat angina?
Yes, by slowing the heart, diastolic perfusion time increases and cardiac oxygen consumption drops (these are good things in the case of angina).
Altogether decreases myocardial oxygen demand.
111
Sympathetic: Beta Blockers:
Which beta blockers are beta-1 selective?
"[A-M]"
ie Atenolol, Betaxolol, Esmolol, Acebutolol, Metoprolol
112
Sympathetic: Beta Blockers:
What is the purpose of using cardioselective beta blockers?
Useful in the acute treatment of MI (<24hrs) and other ACS.
Also useful in the management of chronic heart failure.
113
Sympathetic: Beta Blockers:
Which non-selective Beta blocker can be used in management of chronic heart failure?
Carvedilol
114
Sympathetic: Beta Blockers:
How are beta blocker cardio protective?
Reduce cardiac remodeling by protecting it from excess circulating catecholamines
115
Sympathetic: Beta Blockers:
What is the pt population to best use beta blockers?
Hypertensive patients with HF or post MI
116
Sympathetic: Beta Blockers:
How to beta blockers associate with the renal system?
BB's inhibit production of renin by antagonizing beta 1 receptors at the Juxtoglomerular Apparatus
117
Sympathetic: Beta Blockers:
What is special about Labetalol?
It's a nonselective beta blocker AND an alpha-1 blocker
- used in pregnancy
118
What medication can be used in an hypertensive emergency?
Labetalol due to its combine alpha and beta blocking effects.
Esmolol is good too.
Both administer IV
119
Sympathetic: Beta Blockers:
Which agents are useful in acute management of aortic dissection?
Labetalol, Propranolol, Esmolol
Administer IV
Other BB's can be administered in addition to a vasodilator
120
Sympathetic: Beta Blockers:
Can you use BB's in HOCM?
Yes
121
Sympathetic: Beta Blockers:
Can you use BB's in prophylaxis of migraines?
Yes
ie Metoprolol, Timolol, and Propranolol can be used in the case of episodic migraines
122
Sympathetic: Beta Blockers:
What is the triad treatment for a Thyroid storm?
3 P's
- Propranolol, Propylthiouracil, and Prednisolone
123
Sympathetic: Beta Blockers:
Can you use BB's to treat essential tremor?
Yes
124
Sympathetic: Beta Blockers:
What is the side effect of nonselective beta blockers in a patient with asthma or COPD?
Can worsen the symptoms because antagonism of beta 2 causes bronchodilation
125
Sympathetic: Beta Blockers:
Which BB can be used to treat glaucoma?
Topical Timolol is nonselective. Antagonism of Beta 2 receptors in the ciliary epithelium results in decreased aqueous humor production.
126
Sympathetic: Beta Blockers:
What side effect of BB's can particularly exist in males?
Impotence (lack of erection)
127
Sympathetic: Beta Blockers:
Which medication is a selective beta-1 antagonist with partial agonist activity?
Acebutolol
*should be avoided in patients with BF or hx of MI
128
Sympathetic: Beta Blockers:
Which medication is a nonselective BB with partial agonist activity?
Pindolol
*should be avoided in patients with BF or hx of MI
129
Sympathetic: Beta Blockers:
How can you treat BB toxicity?
Glucagon
