Unit III: The Nervous System

1
Unit III The Nervous System

• Chapter 21
• Drugs for Neuromuscular Disorders

2
Muscle Spasms

• Involuntary contraction of a muscle or group of
  muscles.
• Associated with
• Overuse or local skeletal muscle injury
• Overmedication with antipsychotics
• Other conditions or disorders
• Types
• Tonic
• Clonic

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Treatment

• Pharmacologic

• Nonpharmacologic

• Analgesics
• Anti-inflammatory agents
• Centrally acting skeletal muscle relaxants

• Immobilization (rest)
• Heat or cold applications
• Hydrotherapy
• Ultrasound
• Supervised exercise
• Massage
• Manipulation

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Centrally Acting Skeletal Muscle Relaxants

• Action
• Exact mechanism unknown believed to inhibit
  upper motor neuron activity within brain and
  spinal cord
• Examples
• baclofen (Lioresal)
• metaxalone (Skelaxin)
• tizanidine (Zanaflex

• Prototype cyclobenzaprine (Flexeril) p. 277
• Adverse effects
• Drowsiness, dizziness, dry mouth, sedation,
  ataxia, light-headedness, urinary hesitancy or
  retention, hypotension, bradycardia

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Two Common Medications

• baclofen (Lioresal)
• structurally similar to GABA, inhibits neuron
  activity with the brain and maybe the spinal
  cord.
• Often first choice drug
• Common side effects
• Drowsiness, dizziness, weakness and fatigue

• tizanidine (Zanaflex)
• Centrally acting alpha2-adrenergic agonist that
  inhibits motor neurons mainly at level of spinal
  cord
• Rare hallucinations
• Common side effects
• Dry mouth, fatigue, dizziness, sleepiness

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Benzodiazepines

• Why would benzodiazepines be used to treat
  muscle spasticity?
• When is the use of benzodiazepines indicated?
• Why are they not considered first choice drugs?

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Spasticity

• condition in which certain muscle groups remain
  in a continuous state of contraction
• What is the most common cause of spasticity?
• What motor neurons are damaged?
• What is the characteristic symptom of spasticity?
  
• What other symptoms are experienced with
  spasticity?

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Treatment for Spasticity

• Combination of pharmacotherapy and physical
  therapy
• Antispasmotics
• Surgery indicated in extreme cases

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Direct Acting Antispasmotics

• Action
• Will either block release of Ach (neuromuscluar
  junction) or block calcium release within muscles
  
• Examples
• botulinum toxin A (Botox) or B (Myobloc)
• quinine sulfate (Quinamm)

• Prototype dantrolene (Dantrium) p. 279
• Adverse effects
• botulinum extreme weakness
• dantrolene muscle weakness, drowsiness, dry
  mouth, dizziness, n/v, diarrhea, tachycardia,
  erratic BP, photosensitivity, urinary retention

10
Nursing Considerations

• What is the role of the nurse in antispasmotic
  therapy?
• What needs to be included in client teaching?