Final Exam Review Flashcards
direct acting cholinomimetics
-drug binds and activates muscarinic or nicotinic receptors
-mimics effects of ACh on peripheral organs
Indirect-acting cholinomimetics
-inhibits AChE
-drug that amplifies the effects of endogenous ACh
Nicotine
nicotinic receptor
varenicline
nicotinic receptor
Bethanechol
-muscarinic agonist
-treats atony and urinary retention
-side effects: diarrhea and urinary urgency
Carbachol
-nicotinic and muscarinic agonist
-glaucoma
pilocarpine
-muscarinic agonist
-glaucoma
-increase salivary secretion
CEVIMELINE
-muscarinic agonist
-for dry mouth associated with Sjogren syndrome or radiation damage
organophosphates
-indirect acting cholinomimetics
-very long acting
Pyridostigmine
-indirect acting cholinomimetics
-intermediate to long acting
Edrophonium
-indirect acting cholinomimetics
-short acting
Muscarinic agonists
-act at M2 and M3 receptors
-parasympathetic
M3 receptor activation
-stimulates smooth muscle contraction
-gland secretion
M2 receptor activation
decreases heart rate
effects of muscarinic agonists in glaucoma
-pupillary circular and ciliary muscle contraction
(miosis and cyclospasm)
-open angle of the anterior chamber
-facilitate outflow of aq humor
-reduce IOP
Physostigmine
-indirect acting cholinomimetics
-intermediate to long acting
-glaucoma
Atony
-paralysis of the stomach, bowel, bladder following surgery
Urinary retention
postoperative or postpartum or secondary to spinal
cord injury or disease (neurogenic bladder)
Neostigmine
-indirect acting cholinomimetics
-intermediate to long acting
-treats atony and urinary retention
-side effects: diarrhea and urinary urgency
Sjögren syndrome
-autoimmune disease where glands are attacked by antibodies
-causes dry mouth and dry eyes
toxicity of muscarinic agonists
-cyclopsam of accommodation
-bronchospasm in asthmatics
-diarrhea
0urinary urgency
0sweating
-vasodilation (hypotension: M3 activation)
-reflex tachycardia
-bradycardia (large dose, direct M2 activation)
AChE inhibitors MOA
-increase levels of AChE at synaptic cleft and neuroeffector junctions
-Enhance responses in organs
innervated by parasympathetic
nerves
how do cholinesterase inhibitors treat glaucoma?
-contract ciliary body
-facilitate outflow of aq humor
-reduce IOP
Edrophonium
diagnostic test for myasthenia gravis
long term therapy treatments for myasthenia gravis
-pyridostigmine
-neostigmine is an alternative
neuromuscular blockade
-produced as an adjunct to surgical anesthesia
-using NONDEPOLARIZING neuromuscular relaxants such as PANCURONIUM
pancuronium
-NONDEPOLARIZING neuromuscular relaxant used in surgery
-form of paralaysis
how do you reverse neuromuscular blockade(surgical paralysis)?
-with cholinesterase inhibitors
-neostigmine and edrophonium
treatment for antimuscarinic (atropine) poisoning
-physostigmine (AChE inhibitor)
-works in CNS and peripheral
-reverses signs of muscarinic blockade
Anti-cholinesterase toxicity: muscarinic excess
-miosis
-salivation
-bronchial constriction
-vomiting
-diarrhea
Anti-cholinesterase toxicity: depolarizing neuromuscular blockade
respiratory arrest
Anti-cholinesterase toxicity: CNS involvement
-cognitive disturbances
-convulsions
-coma
Anti-cholinesterase toxicity: cause of death
respiratory failure
treatment of AChE toxicity
-atropine: antagonizes muscarinic receptor sites in both CNS and peripheral organs
-Pralidoxime(2-PAM): cholinesterase regenerator (prevent aging)
Therapy considerations for AChE toxicity
-early treatment is important
-continue drug therapy fir a week or longer
Anticholinesterases for myasthenia gravis testing
Edrophonium (short acting)
Anticholinesterases for myasthenia gravis therapy
-neostigmine: intermediate
-pyridostigmine: long acting
Anticholinesterases for reversal of NM blockade of nondepolarizing neuromuscular relaxants
-edrophonium
-neostigmine
-pyridostigmine
Anticholinesterases for reversal atropine (antimuscarinic) poisoning
-Physostigmine
-lipid soluble
-reverse both central and peripheral muscarinic blockade
Anticholinesterases for glaucoma
-Physostigmine
-lipid soluble
Anticholinesterases for bowel and urinary atony(after surgery or spinal cord injury)
-Neostigmine
Anticholinesterase effects on Neuromuscular junction
-stimulate skeletal muscle contraction
-low dose: prolong and intensity contraction
-high dose: FASCICULATION
-toxic dose: muscle paralysis
Anticholinesterase effects on the eye
-miosis (pupillary circular Ms. Contraction)
-cyclopsam( due to contraction)
-decrease IOP
-
Anticholinesterase effects on the GI
-Increase GI motility: relax sphincter
-increase GI secreation
-side effects: DIARRHEA
Anticholinesterase effects on the genitoururinary tract
-increase detrusor contraction
-relax sphincter
-side effects: URINARY URGENCY
Anticholinesterase effects on the heart/blood vessel
-Side effect: bradycardia(M2 activation)
-no effect on blood vessel
antimuscarinic MOA
-reversible blockade of cholinomimetic action at muscarinic receptors
-m1-m5
anti-muscarinics for motion sickness
Scopolamine
-lipid soluble
anti-muscarinics for retina examination and how long they last
-atropine: long
-scopolamine: long
-homatropine: short
-cyclopentolate: short
-tropicamide: SHORTEST PREFERRED IN PATIENTS WITH NARROE ANTERIOR CHAMBER
anti-muscarinics to prevent synechia formation (tissue adhesion)
-homatropine
-long acting
anti-muscarinics for asthma and COPD
-ipratropium: short
-tiotropium: longer
-aclidinium: longer
-umeclidium: longer
anti-muscarinics for routine preoperative medications (Prevent laryngospasm and
bronchial secretion caused by
inhaled anesthetics)
-atropine
-scopolamine: also has sedative effect
anti-muscarinic effects on the eye
-Mydriasis: pupil dilation
-cycloplegia: relaxation of cilliary muscle
-SIDE EFFECTS: BLURRED VISION (BLIND AS A BAT), INCREASED IOP, DRY EYES
anti-muscarinic effects on the respiratory system
-bronchodilation
-reduce bronchial secretion
anti-muscarinic effects on the GI tract
-reduced motility
-reduced salivation
CONSTIPATION
anti-muscarinic effects on the urinary tract
-relax bladder wall
-side effects: URINARY RETENTION IN BPH PATIENTS
anti-muscarinic effects on the heart
-TACHYCARDIA (due to block of M2 activation in the SA node)
anti-muscarinic effects on the glands (sweat, salivary, lacimal…)
-reduced secretions
-HYPERTHERMERIA(atropine fever in children, hot as hare)
-dry as bone
anti-muscarinic effects for cholinergic poisoning
-block muscarinic excess at both peripheral and CNS
antimuscarinics for IBS and minor diarrhea
-dicyclomine
-hyoscyamine
antimuscarinics for overactive bladder (postoperative spasm, urge incontinence)
-oxybutynin
-darifenacin, solifenacin
-tolterodine, fesoterodine
-trospium, atropine
antimuscarinics for reflex vagal discharge
atropine
antimuscarinics for cholinergic poisoining(insectisides)
-atropine
-pralidoxime
antimuscarinics for mushroom poisoning
atropine
Depolarizing NMJ Blocker (Succinylcholine) MOA
Binds to NM nicotinic receptor and acts like Ach, depolarizing the muscle
Phase I block (Depolarizing)
Membrane depolarizes for a longer period, resulting in an
initial fasciculation (twitching) followed by flaccid/paralysis
Phase II block (Desensitizing):
Membrane repolarized; Receptors are desensitized to
further stimulation, causing flaccid/paralysis.
Depolarizing NMJ Blocker (Succinylcholine) pharmacokinetics
Rapid onset, short duration; metabolized mainly by pseudocholinesterase in the plasma
Depolarizing NMJ Blocker (Succinylcholine) reversal
*Phase I block is augmented, not reversed, by cholinesterase inhibitors *
Side effects of succinylcholine
-hyperkalemia: on patients with burns or trauma, extra N ACh receptor
-increased intragastric pressure
-muscle pain(Myalgias)
-cardiac arrhymias
-malignant hyperthermia
Non-Depolarizing NMJ Blockers MOA at low doses
-act as competitive blockers
-interact with the nicotinic receptors on muscles and prevent Ach from binding
-prevent depolarization
-can be REVERSED by AChE inhibitors (neostigmine,edrophonium, pyridostigmine)
Nondepolarizing NM blocking drugs drug interactions
-NM blockade effect potentiated by inhaled anesthetics (such as isoflurane)
-antibiotics: aminoglycosides
-local anesthetics and antiarrhythmic drugs
Nondepolarizing NM blocking drugs disease/age interactions
-myasthenia gravis: need lower doses
-aging: need lower dose
-patients with severe burns: need higher dose
Depolarizing NM blocking drug (Succinylcholine) drug interactions
antibiotics
-local anesthetics
-anti-arrythmias: potentiate NMB blocking effects
MOA of tubocurarine, cistracurium, rocuronium
competitive antagonist at nACH receptors, especially at neuromuscular junctions
Effect of succinylcholine
-initial depolarization causes transient contractions followed by prolonged flaccid paralysis
-depolarization followed by repolarization then paralysis
clinical applications of succinylcholine
-placement of ET tube
-control of muscle contractions in status epilepticus
clinical applications of tubocuraine
-prolonged relaxation for surgical procedures
-superseded by newer nondepolarizing agents
clinical applications of cistricurium
-prolonged relaxation for surgical procedures
-relaxation for respiratory muscles to facilitate ventilation in ICU
clinical applications of rocuronium
-prolonged relaxation for surgical procedures
-relaxation for respiratory muscles to facilitate ventilation in ICU
-USE IN PATIENTS WITH RENAL INPAIRMENT
midodrine MOA and organ system effects
-a1 agonist
–vascular smooth muscle Ms. contraction
-increase BP
midodrine clinical application
-orphostatic hypotension
midodrine side effects
-supine hypertension
-urinary retention
-piloerection
Phenylephrine MOA and organ system effects
-a1 agonist
-vascular smooth muscle contraction: increase BP
-local vasoconstriction
-mydriasis: pupillary radial MS contraction
Phenylephrine clinical applications
-acute hypotension
-nasal decongestant
-eye exam
clonidine, methyldopa, guanfacine, guanabenz MOA and organ system effects
-a2 agonist
-decrease sympathetic outflow(if taken orally)
-lower BP and bradycardia
clonidine, methyldopa, guanfacine, guanabenz clinical application
hypertension
clonidine, methyldopa, guanfacine, guanabenz side effects
-sedation
-dry mouth
dexmedetomidine MOA and organ effects
-a2 agonist
-CNS effects
dexmedetomidine clinical application
-induce sedation before anesthesia
-combine with opioids
Apraclonidine, brimonidine MOA and organ effects
-a2 agonist
-reduce NE release from presynatic nerves, reduces aq humor production, decrease IOP pressure
Apraclonidine, brimonidine clinical application
glaucoma
Oxymetazoline MOA and organ effects
-a1 and a2 agonist
-local vasoconstriction
Oxymetazoline clinical applications
-nasal decongestants
-facial erythema
Xylometazoline MOA and organ effects
-a1 and a2 agonist
-local vasoconstriction
Xylometazoline clinical applications
-nasal decongestants
Prazosin, Doxazosin, terazosin, alfuzosin MOA and organ effects
-a1 antagonist
-vasodilation: lowers BP
Prazosin, Doxazosin, terazosin, alfuzosin clinical applications
-mild to moderate hypertention
Prazosin, Doxazosin, terazosin, alfuzosin side effects
-orthostatic hypotension after the first few doses
Prazosin, Doxazosin, terazosin, tamsulosin, silodosin MOA and organ effects
-a1 antagonist
-relaxation of smooth muscle in prostate glands
Prazosin, Doxazosin, terazosin, tamsulosin, silodosin clinical application
-urinary obstruction in BPH
-very useful in patients with both BPH and hypertension
prazosin MOA and organ effects
-a1 antagonist
-vasodilation
-relaxes smooth muscle
prazosin clinical applications
-PVD decreased Raynaud’s phenominom
-hypertension
-urinary obstruction in BPH
Yohimbine MOA and organ effects
-a2 antagonist
-increase sympathetic outflow
Yohimbine clinical application
dietary and health supplement
Phenoxybenzamine MOA and organ effects
-irreversible a1 and a2 antagonist
-vasodilation: lower BP
-exaggerate reflex tachycardia
Phenoxybenzamine clinical applications
-hypertension in pheochromocytoma
-PVD (Raynaud’s phenominon)
Phenoxybenzamine side effects
-orthostatic hypotension
-reflex tachycardia(severe)
Phentolamine MOA and organ effect
-reversible a1 and a2 antagonist
-vasodilation: lower BP
-exaggerate reflex tachycardia
Phentolamine clinical applications
-hypertension in pheochromocytoma
Phentolamine side effects
-orthostatic hypotension
-reflex tachycardia(severe)
Dobutamine MOA and organ effects
-B1 agonist
-positive iontropic
-positive chronotropic
-positive dromotropic
Dobutamine clinical application
cardiogenic shock
-acute heart failure
albuterol, terbutaline, metaproterenol MOA and organ effects
-B2 agonist: short acting
-bronchodilation
albuterol, terbutaline, metaproterenol clinical applications
acute asthma syndromes: acute bronchospasms
Almenterol, formoterol MOA and organ effects
-B2 agonist: long acting
-bronchodilation
Almenterol, formoterol clinical applications
-chronic asthma (with steriods)
-COPD
Indacaterol, Olodaterol, vilanterol MOA and organ effects
-B2 agonist: ultralong acting
-bronchodilation
Indacaterol, Olodaterol, vilanterol clinical applications
-chronic asthma (with steriods)
-COPD
Ridodrine, terbutaline MOA and organ effects
-B2 agonist
-uterus relaxation
Ridodrine, terbutaline clinical applications
-suppress premature labor
Mirabegron MOA and organ effects
-B3 agonist
-bladder wall relaxation
-stimulate lipolysis
Mirabegron clinical application
-urinary urgency
Dopamine MOA and organ effects
-D1, b, and a agonist
-vasodilation of renal blood vessels(D1)
-increase C.O(B1)
-both increase renal blood flow
Dopamine clinical applications
-oliguria
-shock with renal failure(avoid overdose)
Fenoldopam MOA and organ effects
-D1 agonist
-vasodilation of renal blood vessels
Fenoldopam clinical applications
-hypertensive emergency (severe hypertension)
Epinephrine MOA and organ effects
-a and b agonist
-local vasoconstriction(a1)
-brochodilation(b2)
-vasoconstriction(a1)
-cardiac stimulant(B1)
Epinephrine clinical application
-used with local anesthetics
-anaphylactic shock
-resuscitation after cardiac arrest
Norepinephrine MOA and organ effects
-a and b agonist
-vasoconstriction(a1)
-mild cardiac stimulant(B1)
Norepinephrine clinical application
acute hypotension and shock
labetalol and carvedilol MOA and organ effects
-B> a1 blocker
-lowers BP with limited HR increase
labetalol and carvedilol clinical applications
hypertension
heart failure
propranolol, nadolol, timolol MOA and organ effects
-block B1 and B2
-lower heart rate and BP
-reduce renin
propranolol, nadolol, timolol clinical applications
-hypertension
-angina pectoris
-arrhythmia
-migraine
-hyperthyroidism
-glaucoma(topical timolol)
propranolol, nadolol, timolol side effects
-bradycardia
-worsened asthma
-fatigue
-vivid dreams
-cold hands
metoprolol, atenolol, betaxolol, nebivolol MOA and organ effects
-block B1>B2
-block HR and BP
-reduce renin
-may be safer in asthma
metoprolol, atenolol, betaxolol, nebivolol clinical application
-angina pectoris
-hypertension
-arrhythmias
-glaucoma(topical betaxolol)
metoprolol, atenolol, betaxolol, nebivolol side effects
-bradycardia
-fatigue
-vivid dreams
-cold hands
Butoamine MOA and organ effects
-blocks B2>B1
-increases peripheral resistances
Butoamine clinical application
none
-makes asthma worse
pindolol, acebutolol, carteolol, MOA and organ effects
-B1, B2, with intrinsic sympathomimetic (partial agonist) effect
-lower BP
-modestly lower HR
pindolol, acebutolol, carteolol, clinical applications
-hypertension
-arrhythmias
-migraine
-may avoid worsening of bradycardia
pindolol, acebutolol, carteolol, side effects
fatigue
-vivid dreams
-cold hands
Esmolol MOA and organ effects
-B1>B2 blocker
-very brief cardiac B blockade
Esmolol clinical applications
-rapid control of BP and arrhythmias
-thyrotoxicosis
-myocardial ischemia intraoperatively
