Cholinergics Flashcards
Carbachol description
non selective muscarinic and nicotoinic receptor agonist
Carbachol actions
used as ocular agent because it causes miosis and increases aqueous humor outflow
Carbachol Indications
open angle glaucoma
Carbachol Toxicity
DUMBBEELSS, but topical so not liekly
Carbachol
-What is the duration of activity and why?
long because it’s not efficiently broken down by AChE
Bethanechol Description
non selective muscarinic receptor agonist
Bethanechol Actions
used to increase detrusor muscle tone and GI motility post op
Bethanechol Indications (3)
urinary retention,
neurogenic bladder
GERD
bethanechol Toxicity (3)
reflex tachy from vasodilation
bronchoconstriction
increased secretory activity (sweat, GI, respiratory secretions)
Bethanechol Route
Oral
Pilocarpine brand name
Salagen
Pilocarpine descrption
non selective muscarinic receptor agonist
Pilocarpine actions
muscarinic receptor activations
Pilocarpine Indications (4)
glaucoma–acute angle and open
dry mouth/xerostomia
sjogren syndrome
head and neck cancer associated radiation
Pilocarpine Toxicity
reflex tachy from vasodilation
bronchoconstriction
increased secretory activity (sweat, GI, respiratory secretions)
Pilocarpine Route (2)
eye drops
oral
Methacholine Description
non selective muscarinic agonist
Methacholine Action
used to diagnose bronchial hyperactivity ie methacholine challenge
Methacholine Indications
only used for asthma diagnosis
Methacholine Route
inhaled only
Varenicline brand name
Chantix
Varenicline description
Nicotinic receptor partial agonist
Varenicline Actions
as a partial agonist it reduces cravings for and decreases the pleasurable effects of cigarettes by inhibiting the ability of nicotine to stimulate the mesolimbic dopamine system
Varenicline Indications
smoking cessation
nicotine withdrawal
Varenicline Toxicity
bronchospasm
nicotine dependence transference
Varenicline route
oral
Nicotine route (3)
gum, patch nasal
metoclopramide description
indirect acting presynaptic cholinomimetic
metoclopramide action
acts by stimulating presynaptic receptors to trigger ACh release
Edrophonium Description
short acting reversible AChE inhibitor/ indirect agonist
Edrophonium action
blocks AChE
Edrophonium Indications
used to diagnose myasthenia gravis
Edrophonium Toxicity
DUMBBEELSS
Edrophonium brand name
tensilon
Edrophonium Half life
10-30 minutes
Edrophonium route
IV
Does Edrophonium cross BBB
highly charged does not cross BBB
Neostigmine description
intermediate length reversible cholinesterase inhibitor
Neostigmine Action
increases acetylcholine availability
Neostigmine indications (3)
Myasthenia Gravis
nondepolarizing neuromuscular blockade reversal
urinary retention
Neostigmine Toxicity
DUMBBEELSS
Neostigmine routes
3
IV
IM
SC
Does neostigmine enter CNS?
no
Pyridostigmine descrption
intermediate length reversible cholinesterase inhibitor
pyridostigmine action
stimulates nicotinic and muscarinic ACh receptors
pyridostigmine indications
myasthenia gravis treatment
pyridostigmine toxicity
DUMBBEELSS
pyridostigmine oral bioavailability (qualitiative)
low
Does pyridostigmine cross the BBB?
no
Physostigmine description
intermediate length reversible cholinesterase inhibitor
physostigmine actions
stimulates nicotinic and muscarinic receptors
physostigmine indications (5)
glaucoma
alzheimers
delayed gastric emptying
undo anticholinergic toxicity/overdose in CNS
non depolarizing neuromuscular blockade reversal
physostigmine toxicity
DUMBBEELSS
physostigmine route 2
IV
IM
does physostigmine cross BBB
yes, so not used for MG treatment
Donepezil brand name
Aricept
other dugs in Donepezil class
Rivastigmine
Galatamine
Donepezil description
intermediate length reversible cholinesterase inhibitor
Donepezil actions
indirectly stimulates nicotinic and muscarinic recpetors
Donepezil Indications
Alzheimer’s associated dementia
Donepezil Toxicity
GI upset
does donepezil cross BBB?
yes
Donepezil bioavailability
100%
Rivastigmine
- description
- indications
- route
intermediate length reversible AChE inhibitor (same class as Donepezil)
-GI UPset
_patch
Galantamine description
AChE inhibitor (same class as Donepezil) and Nn agonist)
Echothiphate description
long acting irreversible cholinesterase inhibitor
Echothiophate action
binds irreversibly to AChE
Echothiophate indications
glaucoma
topical
Echothiophate toxicity (2)
lacrimation
stinging
Echothiphate indications
glaucoma
echothiophate route
topical b/c very long half-life
Atropine drugs in same class (2)
homatropine
tropicamide
Atropine description
direct muscarinic antagonist
Atropine Action
prevents ACh binding
so lowers activity of muscles and glands regulated by PNS
Atropine Indications (4)
organophosphate poisoning (given w/ pralidoxime)
pupil dilation
bradycardia
reduce secretions
Atropine Toxicity (9)
mad as a hatter blind as a bat dry as a bone red as a beet hot as a hare urinary retention bronchodilation constipation tachy
Atropine Route (3)
SC
IM
IV
Pralidoxime aka
2-PAM
Pralidoxime Description
reactivates cholinesterase
Pralidoxime Actions
Binds to organophosphate and accelerates AChE reactivation
Pralidoxime/ 2-PAM toxicity
anticholinergic effects
pralidoxime/ 2 pam route (2)
IV
IM
which drug does military have stockpile of self-injectors
pralidoxime
Benztropine brand name
cogentin
benztropine description
muscarinic (some m1 specificity)
histamine receptor blockade
Benztropine actions
centrally acting anticholinergic/antihistamine agent
Benztropine indications
parkinsonism
dystonia
extrapyramidal symptoms
Benztropine toxicity
anticholinergic
Benztropine route (2)
IM
IV
Scopolamine description
muscarinic blocker
scopolamine actions
blocks muscarinic receptors, some M1 specificity
anti-emetic
Scopolamine Indications (2)
motion sickness
dilate eyes
Scopolamine Toxicity
anticholinergic
Scopolamine Route (2)
transdermal
can Scopolamine cross BBB
yes
Ipratropium brand name
Atrovent HFA
Ipratropium —similar drug in same class
Tiotropium
Ipratropium Description
muscarinic blocker
Ipratropium action
inhaled bronchodilator (M3)
Ipratropium indications (2)
asthma
COPD
Ipratropium toxicity
rare and only through overdosing
dry mouth and sedation
other anticholinergic effects
Ipratropium route
inhaled
is ipratropium faster or slower than Beta 2 agonists?
slower
ipratropium duration
6-8 hrs
tiotropium brand name
Spiriva
Dicyclomine brand name
Bentyl
Dicyclomine Description`
non-selective muscarinic receptor blocker
dicyclomine actions
relaxes smooth muscle
inhibits bradykinin and histamine induced bowel spasms
dicyclomine indications
IBS
dicyclomine toxicity
anticholinergic
dicyclomine route
oral
Glycopyrrolate description
muscarinic blocker
oxybutinin description
muscarinic blocker
Succinylcholine Description
Depolarizing nicotinic NMJ blocker and ACh receptor agonist
Succinylcholine Actions
complete muscle relaxation’
flaccid paralysis
Succinylcholine indicaitons
short term muscle relaxation in anesthesia, ICU, intubation
Succinylcholine Toxicity (3)
rhabdomyolysis w/ hyperkalemia w/ ventricular dysrhythmias
cardiac arrest
death if given to peeps with undiagnosed myopathy
Succinylcholine route
IV
succinylcholine contraindication
patient lacking AChE
succinylcholine caveat
can’t be reversed
Tubocurarine description
Benzylisoquinoline Non depolarizing Nm NMJ blocker –reversible
Tubocurarine actions
blocks Nm receptor and leads to flaccid skeletal paralysis
Tubocurarine indications
muscle relaxation for surgery
Tubocurarine roxicity
6
respiratory failure paralysis in fully conscious tachy hypertension histmaine release ganglionic and muscarinic side effects
Tubocurarine duration
30-60 minutes
What drug is primarily used to reverse nondepolarizing nicotinic NMJ receptor blockers
neostigmine
Pancuronium description
aminosteroid nondepolarizing nicotinic NMJ receptor blocker
Vercuronium Description
aminosteroid nicotnic NMJ blocker, reversible
Vercuronium actions
flaccid paralysis
Vercuronium indication (2)
muscle relaxer for surgery
used for executions
Vercuronium toxicity (6)
special training required for admin respiratory failure paralysis in awake individual tachycardia HTN histamine release ganglionic and muscarinic side effects
Vercuronium duration
30-60 minutes
Vercuronium caveat
caution with hepatic impairment
aminosteroids are what class of cholinergic
non depolarizing nicotinic NMJ blocker
Benzylisoquinolines are what class of cholinergic?
non depolarizing nicotinic NMJ blocker
Cisatracurium brand name
nimbex
Cisatracurium descrption
Benzylisoquinoline Nm NMJ blocker–reversible
Cisatracurium actions
blocks receptors and leads to flaccid skeletal muscle paralysis
Cisatracuriumindications
muscle relaxation for surgery
Cisatracurium toxicity
respiratory failure paralysis in fully conscious patients tachycardia HTN histamine release ganglion and muscarinic effects
Cisatracurium duration
30-60 minutes
Rocuronium description
aminosteroid nondepolarizing nicotinic NMJ receptor blocker
Trimethaphan description
Nn ganglionic blocker –reversible
Trimethaphan brand name
arfonad
Tubocurarine brand name
curare
Trimethaphan indications
rarely used in hyertensive crisis or dissecting aortic aneurysm
Botox descrption
inhibitor of ACh release
Botox Actions
interferes w/ vesicle docking proteins on interior of nerve membrane , so ACh can’t be released
Botox indications
wrinkles muscle weakness diplopia blurred vision ptosis dysphagia dysphonia dysarthria urinary incontinence breathing difficulties
M1 receptors
- located where
- mechanism
- 2nd messenger
- Action
nerve endings
Gq
increased IP3 and DAG cascade
activate myenteric plexus
M2 receptors
- located where
- mechanism
- 2nd messenger
- Action
heart
Gi
decreased CAMP, activate K channels
slows SA Node/ HR
M3 receptors
- located where
- mechanism
- 2nd messenger
- Action
smooth muscles, glands, endothelium
Gq
increased IP3, DAG
contract detrusor muscle, increase secretions
Nn
- located where
- mechanism
- 2nd messenger
- Action
ANS ganglia
N-K ion channel
Na
depolarizes postganglionic fiber and evokes AP
Nm
- located where
- mechanism
- 2nd messenger
- Action
NMJ
Na-K ion channel
Na
depolarizes muscle cell–leads to contraction
DUMBBEELSS for acetylcholine overdose stands for
diarrhea urination miosis bronchorrhea bradycardia excitation of skeletal muscles emesis salivation sweating
What are signs of anticholinergic overdose?
mad as a hatter- delirium Blind as a bat: mydriasis--dilation and lack of accomodation Dry as a Bone: reduces secrtions Hot as hare: elevated body temp Red as a beet: skin flushing urinary retention: bronchodilation constipation tachycardia HTN
