Muscle Relaxants/Spasmolytic

Question 0

Succynlycholine

Answer 0

-muscle relaxant
MOA: keeps channel open and prevents hyperpolarization=can’t reset (agonist)
Clinical
-surgical relaxation, tracheal intubation, control of ventilation, treatment of convulsions
ADE
-Cardiac arrhythmias, hyperkalemia, increased intraocular pressure, increased intraogastric pressure, muscle pain
“sucks w/ mouth open”

Question 1

Rocuronium

Answer 1

-muscle relaxant
MOA: competes with ACh and blocks ACh receptors (Na channel)-no depolarization=no AP
-antagonist
Clinical
-surgical relaxation, tracheal intubation, control of ventilation, treatment of convulsions
ADE
-Cardiac arrhythmias, hyperkalemia, increased intraocular pressure, increased intraogastric pressure, muscle pain
“blocks like a rock”

Question 2

Neostigmine

Answer 2

MOA: inhibits cholinesterase=inc ACh concentration
-antagonist to rocuronium
-used to restore muscle function
“neo stops esther”

Question 3

Diazepem

Answer 3

-spasmolytic drug
MOA: increases inhibition of motor efferent spinal cord=allows Cl to come in and hyperpolarize
-GABA(A) receptors
Clinical
-treat spasms in cerebral palsy, stroke, spinal chord injury, acute spasm
ADE
-sedation of dosages needed to reduce muscle tone
-ionotropic receptor

Question 4

Baclofen

Answer 4

-spasmolytic drug
MOA
-GABA(B) receptor agonist
-leads to reduced excitatory neurotransmitters in brain
-presynaptic-inhibit Ca, hyperpolarize via K exit
-post synaptic - prevent release of vesicles/AP
Clinical
-treatment of spasms for cerebral palsy, multiple sclerosis, and stroke
Good
-less sedation than diazepam, no reduction in muscle strength compared to dantrolene
-metablotrophic receptor

Question 5

Tizanidine

Answer 5

-spasmolytic drug
MOA
-Alpha2 adrenoreceptor receptor agonist
-inhibition in both pre and post synapses in spinal chord and pain transmission in spinal dorsal horn
Clinical
-treatment of spasms for Multiple sclerosis, stroke, amyotrophic lateral sclerosis
ADE
-drowsiness, hypotension, dry mouth, asthenia

Question 6

Dantrolene

Answer 6

-spasmolytic drug
MOA: blocks ryanodine receptor (RyR) on sarcoplasmic reticulum=reduces skeletal muscle strength by inhibiting Ca release
Clinical
-treatment of spasms for cerebral palsy, spinal cord injury, multiple scerosis and malignant hyperthermia
ADE
-muscle weakness
“hot rhino w/ dandruff”,

Question 7

Cyclobenzaprine

Answer 7

-spasmolytic drug
Clinical
-used for acute muscle spasm by local trauma
-ineffective in treating spasm due to cerebral palsy or spinal cord injury
ADE
-sedation, visual hallucinations, confusion