Drugs for Neuromuscular Disorders and Muscle Spasms Flashcards
is an acquired autoimmune disease that impairs the transmission of messages at the neuromuscular junction, resulting in varying degrees of skeletal muscle weakness that increases with muscle use
myathenia gravis (MG)
___ may result from respiratory muscle paralysis in MG
respiratory arrest
the symptoms of MG are caused by autoimmune destruction of ___ sites and a resultant decrease in neuromuscular transmission
ACh
patho of MG
autoimmune process in which antibodies attack ACh receptors. The result is a decreased amount of AChR sites at the neuromuscular junction. This prevents ACh molecules from attaching to receptors and stimulating normal muscular contraction
when muscular weakness in the patient with MG becomes generalized, ___ can occur. This complication is a severe, generalized muscle weakness that involves the muscles of respiration, such as the diaphragm and intercostal muscles
myathenic crisis (underdose of AChE inhibitors dose q 2-4 hrs to prevent)
if the muscle weakness from a myathenic crisis remains untreated, death can result from paralysis of the respiratory muscles.
____ a fast-acting AChE inhibitor, can relieve a myathenic crisis
neostigmine
overdosing with AChE inhibitors may cause another complication if MG called ____
is an acute exacerbation of symptoms
cholinergic crisis
a cholinergic crisis usually occurs within ___ after taking anticholinergic drugs
30-60 min
symptoms/manifestations of MG
weakness of skeletal muscles, ptosis, diplopia, dysphagia, dysarthria (slurred speech), and respiratory muscle weakness
common triggers of a myatheic crisis
underdose of AChE inhibitors, infection, emotional stress, menses, pregnancy, surgery, trauma, hypokalemia, temp extremes, and alcohol intake
manifestations of cholinergic crisis
miosis, pallor, sweating, vertigo, excessive salivation, N/V, abdominal cramping, diarrhea, bradycardia
what is the AChE inhibitor that is given to differentiate between a myathenic and cholinergic crisis
edrophonium chloride
an intermediate acting AChE inhibitor that is given IV undiluted for treatment of MG
pyridostigmine
what is the antidote to an AChE inhibitor like pyridostigmine
atropine (anticholinergic)
patients who do not respond to AChE inhibitors may require additional drug treatment such as ___
prednisone, plasma exchange, IV immune globulin, or immunosuppressive drugs (azathioprine)
monitor CBC and LFTs
an autoimmune disorder that attacks the myelin sheath of nerve fibers in the brain and spinal cord, which results in lesions called plaques
Multiple Sclerosis (MS)
a condition with remissions and exacerbations
motor symptoms of MS
weakness or paralysis of limbs, muscle spasticity
Diagnostics used to diagnose MS
medical hx, neurological exam, MRI, evoked potential (test that measures the electrical activity of the brain)
disease-modifying drugs and are the first line treatment for pts with MS
can slow the progression of the disease and prevent relapse
immunodulators
**interferon beta 1-a and 1-b
relieve muscular spasms and pain associated with traumatic injuries and spasticity from chronic debilitating disorders
skeletal muscle relaxants
depress neuron activity in the spinal cord or brain and enhance neuronal inhibition of the skeletal muscles
centrally acting muscle relaxants
example of a centrally acting muscle relaxant and implications
cyclobenzaprine
no alcohol, no pregnancy, take w/ food, and at bedtime
take a week to taper
used for acute muscle spams do not take > 3 wks
muscle relaxants used for skeletal muscle spasticity and muscular hyperactivity that causes contraction of the muscles, resulting in limited pain and mobility
baclofen, dantrolene, tizanidine
do not take with other depressants
