What is Parkinson's Disease
Neurological disorder that affects the extrapyramidal system (posture, balance, locomotion)
What affects does Parkinsons disease cause on the body?
Bradykinesia (the slowing of movement), akinesia (the complete absence of movement), tremors, rigidity, and postural instability
What causes Parkinsons disease/
An imbalance of dopamine and acetylcholine
What are the 5 categories of drugs that treat PD?
Anticholinergics, Dopaminergics, Dopamine agonists, MAO-B inhibitors, and COMT inhibitors
What is the therapeutic goal of PD treatments?
Restore DA/ACh balance by increasing DA and decreasing ACh, restore the patients ability to carry about ADL, and reduce the symptoms (reduce rigidity and tremors and increase mobility)
Drug of choice for PD. It is metabolized quickly and is needed in large doses to see response. Therapeutic responses may take months to develop and will lose effect after use for more than 5 years. Many adverse effects occur such as: N/V, dyskinesia, "on-off" phenomenon, cardiac, psychiatric, darkened sweat/urine, and activation of malignant melanoma
The most effective therapy for PD. It allows the dosage of Levodopa to be reduced by inhibiting the enzyme that breaks down levodopa so more can enter the brain. It also allows for a single daily dose.
What is Myasthenia Gravis?
Lack of nerve impulses and muscle response due to a lack of Ach.
How does Myasthenia Gravis affect the body?
Results in fatigue, muscle weakness of the respiratory system, facial muscles, and extremities, cranial nerve palsies, ptosis, dysphagia, and trouble chewing
What is Alzheimers disease?
Neurodegenerative condition with cognitive dysfunction that can only be completely diagnosed after death by examining the brain with a microscope for plaques and tangles
How do cholinesterase inhibitors treat alzheimer's disease?
By preventing the breakdown of ACh and stimulating nicotinic receptors to release more ACh in the brain
How do NMDA antagonists work to treat alzheimer's disease?
By blocking the toxic effects associated with excess glutamate and regulating glutamate action
Explain the difference between a muscle spasm and muscle spasticity
Spasm: a sudden, violent, involuntary contraction of a muscle or group of muscles r/t injury and motor neuron diseases (Cerebral palsy, MS, spinal cord injury, CVA)
Spasticity: certain muscles are continuously contracted
Muscle relaxant that works by supressing hyperactive reflexes in the spinal cord. It has no effects on the skeletal muscles. It reduces spasticity associated with MS, spinal cord injury, and cerebral palsy, but NOT a stroke
What will CNS depressants do? Give examples.
Increase sedation. Alcohol, opiods, benzodiazepines, and barbiturates
What is multiple sclerosis?
An autoimmune disease characterized by the presence of multifocal regions of inflammation and myelin destruction in the CNS. After attacks, there appears to be some degree of recovery, but with recurrent episodes recovery becomes less
What are the signs and symptoms of MS?
It depends on the level of demyelination: paresthesias, muscular/motor problems, visual impairment, bladder and bowel symptoms, sexual dysfunction, fatigue, emotional liability, depression, cognitive impairment, slurred speech, dysphagia, dizziness, vertigo, and neuropathic pain
What are the MS subtypes?
Relapsing-Remitting MS (recurrent, defined episodes of neurologic dysfunction, separated by periods of partial or full recovery)
Secondary Progressive MS (pt with relapsing-remitting MS develops steadily worsening function)
Primary Progessive MS (symptoms grow progressively intense, although there may be periods of occasional plateaus or improvements)
Progressive-Relapsing MS (rare; looks like primary MS but has acute exacerbations superimposed on the steady intensification of symptoms)
What is the therapeutic goal for disease modifying drugs for MS? What are the two groups?
To decrease the frequency and severity of relapses, reduce the development of brain lesions, decrease future disability, and help maintain quality of life.
What is the treatment for acute relapses of MS?
A short term, high dose use of glucocorticoid IV therapy to suppress inflammation and thereby reduce the severity and duration of the attack OR use of IV gamma globulin for patients who cannot tolerate gluococorticoids
What is epilepsy?
A group of disorders in the CNS that are characterized by excessive excitability of neurons. Epilepsy may produce a variety of symptoms such as a brief period of unconsciousness to violent convulsions.
What are seizures? What are the subtypes?
Initiated by synchronous, high frequency discharge of neurons in a group called a focus.
1. Partial seizures
2. Generalized seizures
3. Mixed seizures/ Lennox-Gastaut Syndrome)
How do antieptileptic drugs work? What is there mechanism of action?
1. Suppress sodium influx (suppresses seizures that depend on high frequency discharge)
2. Supress calcium influx (calcium promotoes transmitter release; suppressing calcium influx suppresses transmission)
3. Glutamate antagonist (glutamate is the primary excitatory neurotransmitter, so by suppressing glutamate, neuronal excitation is suppressed)
4. Potentiate GABA (GABA is an inhibitory neurotransmitter, so by augmenting the inhibitory influence of GABA, the neuronal excitability and seizure activity is suppressed)
What are the cautions of antiepileptic drugs?
Trial period, evaluation, plasma drug levels, patient adherence, withdrawing medication, and suicidal risk
What is Generalized Convulsive Status Epilepticus?
A life threatening continuous series of tonic-clonic seizures that last 20-30 minutes. Tachycardia, elevated blood pressure, and hyperthermia may be present. Metabolic acidosis and hypoglycemia may occur. SE can cause permanent neurological injury and death.
How do skeletal muscle relaxants work?
They relieve muscle spasm and pain by suppressing hyperactive reflexes from excitable neurons in the CNS.
*Older adults are more prone to the sedation and anticholinergic effects