Module 9: Meds For Neurodegenerative And Seizure Disorders

Question 1

What is the main inhibitory neurotransmitter?

Answer 1

GABA (gamma-aminobutyric acid)

Question 2

How does GABA work?

Answer 2

works by decreasing brain activity.
Although different classes of CNS depressants work in unique ways, ultimately it is their ability to increase GABA activity that produces a drowsy or calming effect.

Question 3

What is the inhibitory neurotransmitter which maintains mood balance?

Answer 3

Serotonin

Question 4

What is the inhibitory and excitatory neurotransmitter which regulates movement and emotional response? Also helps to regulate reward and pleasure centres in the brain

Answer 4

Dopamine

Question 5

What is the neurotransmitter which has an excitatory action related to mood, motor activity, arousal and reward?

Answer 5

Norepinephrine

Question 6

Neurotransmitter whose excitatory action regulates movement and memory?

Answer 6

Acetylcholine

Question 7

What is Parkinson’s disease?

Answer 7

Degenerative disorder of the CNS caused by death of the neurons that produce dopamine

Question 8

What is the underlying neurotransmitter imbalance in PD?

Answer 8

Lack of dopamine activity and a related hyperactivity of acetylcholine

Question 9

What is PD characterized by?

Answer 9

tremors, muscle rigidity, bradykinesia (slowness of movements, poor fine motor skills), postural instability, limb stiffness, difficulties with gait and balance

Question 10

What are the goals of pharmacotherapy to manage PD?

Answer 10

Restore dopamine function (Dopamine Agonists)

Block the effect of ACh (Anticholinergics)

Question 11

What is the drug of choice for Parkinson’s disease?

Answer 11

Levodopa, enhanced by combination with carbidopa (Sinemet)

Question 12

Why is dopamine not used for therapy for PD?

Answer 12

Dopamine cannot cross the blood brain barrier, levodopa can

Question 13

Dopaminergics - Muscle twitching and mood changes may indicate what?

Answer 13

Toxicity

Question 14

What is the role of anticholinergics in managing PD?

Answer 14

Decrease the activity of acetylcholine
- Not as effective as other agents, therefore mostly used in early onset PD
- Mainly used to control tremor and ease dystonia
Example: benztropine (Cogentin)

Question 15

What class of drug is most widely used for treatment of Alzheimer’s disease?

Answer 15

Acetylcholinesterase (AChE) inhibitors (indirect
acting cholinergics)
- intensifies the effect of acetylcholine at the cholinergic receptors

Question 16

Drug therapy for Alzheimer’s disease focusses on…

Answer 16

Restoring or enhancing acetylcholine’s role in the brain

Question 17

Multiple sclerosis is a neurodegenerative disease characterized by

Answer 17

Demyelination (destruction or removal of the Myelin sheath from a nerve or nerve fibre)

Question 18

What is a seizure?

Answer 18

A disturbance of electrical activity in the brain that may affect consciousness, motor activity, and sensation
- symptoms are caused by abnormal or uncontrollable neuronal discharges within the brain

Question 19

What tool is used in diagnosing seizure disorders?

Answer 19

EEG

Question 20

There are three general mechanisms by which anti-seizure medications act to suppress neuronal activity to prevent abnormal firing:

Answer 20

1) Increase the action of GABA
2) Delay an influx of sodium ions
3) Delay an influx of calcium ions (not covered in this course)

Question 21

Anticovulsants: How do barbiturates work? what are the side effects?

Answer 21

• Enhances the inhibitory neurotransmitter GABA, thereby depressing CNS
-Low margin of safety, considered a controlled substance
• Adverse/side effects: Respiratory depression, sedation, confusion (similar effects of narcotics)

Question 22

Anticonvulsants: describe Benzodiazepine

Answer 22

• Enhances the inhibitory neurotransmitter GABA, thereby depressing CNS
• Used for short period of time
• Manage acute frequent small seizures
• Adverse/side effects: sedation, respiratory depression

Question 23

Anticonvulsants: how do Hydantoins and phenytoin-like drugs work? Side effects?

Answer 23

• Suppress Na+ influx by desensitizing Na+ channels
• Adverse/side effects: Cardiovascular changes, sedation
• Nursing considerations:
- Monitor serum drug levels
- S/sx of hydantoin toxicity?
- Phenytoin may change urine color to pink or brown