Skeletal muscle relaxants (kruse)

Question 1

prototype nondepolarizing neuromuscular blocking drug and its MOA?

Answer 1

tubocurarine:

MOA: competitive antagonist at ACh binding site on nAChRs

prevents depol of muscle membrane and blocks contraction

Question 2

prototype depolarizing neuromuscular blocking drug and its MOA?

Answer 2

succinylcholine: blockade produced by excess of depolarizing agonist

Question 3

Baclofen, carisoprodol cyclobenzaprine, diazepam, and tizanidine are what type of muscle relaxants (spasmolytics)?

Answer 3

centrally acting

Question 4

dantrolene and botulinum toxin are what type of spasmolytics

Answer 4

non-centrally acting

Question 5

glucocorticoids, glatiramer acetate, IFN-B1a and IFN-B1b are immunologic drugs for __

Answer 5

MS

Question 6

pralidoxime is a __ reactivator

Answer 6

cholinesterase

Question 7

agent utilized to support dx of myasthenia gravis?

Answer 7

edrophonium (tensilon test)

this is an Ach-esterase inhibitor

Question 8

effects of usage of Ach-esterase inhibitors?

Answer 8

Parasympathetic effects

Question 9

what type of ACheE inhibitors cross the BBB and are inappropriate d/t CNS adverse effects?

Answer 9

lipid-soluble (Ie., physostigmine)

others: donepezil, rivastigmine, galantamine, tacrine, organophosphates

Question 10

glycopyrrolate, propantheline, hyoscyamine, and atropine are what type of compounds?

Answer 10

anti-muscarinic

Question 11

__ is the only depolarizing blocking drug used clinically. It produces muscle fasciculations and for anesthesia

Answer 11

succinylcholine

Question 12

atracurium, cisatracurium, rocuronium, vecuronium are examples of what type of neuromuscular blockers?

Answer 12

nondepolarizing, intm acting

maintain muscle relaxation during anesthesia

Question 13

__ is for tx of malignant hyperthermia and mgmt of spasticity associated w/ motor neuron disorders (MS, cerebral palsy, SC injury, stroke)

Answer 13

dantrolene

Question 14

MOA of dantrolene?

Answer 14

directly binds to sk. m. RYR1 and inhibits further Ca release (antagonist)

Question 15

adverse effects of nondepolarizing agents?

Answer 15

• effects last too long
• profound hypotension
• histamine release –> bronchospasm, hypotension, bronchial and salivary secretion

Question 16

signs/symptoms of organophosphate overexposure?

Answer 16

S-Salivation
L-Lacrimation
U-Urination
D-Defecation
G-GI pain and gas
E-Emesis

Question 17

Tx for AChE inhibitor poisoning?

Answer 17

Atropine (mAChR antagonist)

Pralidoxime (Cholinesterase regenerator)

Question 18

Pralidoxime provides relief by acting at which receptor?

Answer 18

nAChR

Question 19

Baclofen is an agonist at __ receptors which results in hyperpolarization and inhibition of excitatory NT release in brain and SC

Answer 19

GABAb

-used to tx reversible spasticity associated wtih MS or SC lesions

Question 20

This spasmolytic is metabolized to meprobamate, which has anxiolytic and sedative effects.

Answer 20

Carisoprodol

Question 21

CYP enzyme that metabolizes Carisprodol?

Answer 21

CYP2C19

Use with caution when administered with CYP450 inhibitors

Question 22

this spasmolytic has an unclear MOA, reduces tonic somatic motor activity by influencing both alpha and gamma motor neurons. It is structurally related to TCA’s and produces antimuscarinic side effects. Metabolized by CYP450’s

Answer 22

Cyclobenzaprine

Question 23

this spasmolytic promotes (FACILITATES) binding of major inhibitory NT in the CNS gamma-GABA to the GABAa receptor, enhancing GABA-induced ion currents (increase frequency). This leads to increased inhibitory transmission and reduction in spasticity

Answer 23

Diazepam

Question 24

MOA of Tizanidine and uses?

Answer 24

a-2 agonist, decreases excitatory input to alpha motor neurons

tx of muscle spasticity

Question 25

__ causes inhibition of RyR Ca channel; blocks release of Ca through SR and muscle contraction is impaired. It is used to tx spasticity of UMN disorders and mgmt of malignant hyperthermia

Answer 25

Dantrolene

Question 26

pts w/ dementia associated with PD can benefit from __

Answer 26

tertiary AChesterase inhibitors

Tacrine, rivastigmine, galantamine, donepezil, physostigmine

The TACky RIVer GALA was DONE after PHYllis took a TERd”
(TERD for tertiary) = Tacrine, rivastigmine, galantamine, donepezil, physostigmine

Question 27

MOA of botulinum toxin?

Answer 27

cleaves components of SNARE, prevent release of Ach

Question 28

this biologic for MS is a mix of polymers of AA’s that is antigenically similar to myelin basic protein

Answer 28

glatiramer acetate

Question 29

__ is used for MS, acts on BBB, interferes with T cell adhesion to endothelium by bidning VLA-4 on T cells

Answer 29

IFN’s

Question 30

__ is an antineoplastic agent for MS, intercalates into DNA resulting in cross-links and strand breaks

Answer 30

mitoxantrone

Question 31

toxicities associated with aminoglycosides?

Answer 31

Nephrotoxicity, ototoxicity, and NM BLOCKADE

Myasthenia gravis is an ABSOLUTE contraindication to aminoglycoside use