Parkinsons

Question 1

What is Parkinson’s?

Answer 1

Parkinson’s disease is a condition where there is a progressive reduction in dopamine in the basal ganglia, leading to disorders of movement

Question 2

Are Parkinson’s symptoms symmetrical or asymmetrical?

Answer 2

Asymmetrical

Question 3

What is the classic triad of symptoms of Parkinson’s?

Answer 3

• Resting tremor (a tremor that is worse at rest)
• Rigidity (resisting passive movement)
• Bradykinesia (slowness of movement)

Question 4

Where in the basal ganglia is dopamine produced?

Answer 4

Substantia nigrans

Question 5

What are the features of the tremor in Parkinson’s? (4)

Answer 5

Asymmetrical
4-6hz frequency
Pill rolling
Worse when distracted (at rest)

Question 6

What type of rigidity is present in Parkinson’s?

Answer 6

Cogwheel rigidity

Question 7

How does Bradykinesia present in Parkinson’s? (6)

Answer 7

• Handwriting gets smaller and smaller (micrographia)
• Small steps when walking (“shuffling” gait)
• Rapid frequency of steps to compensate for the small steps and avoid falling (“festinating” gait)
• Difficulty initiating movement (e.g., going from standing still to walking)
• Difficulty in turning around when standing and having to take lots of little steps to turn
• Reduced facial movements and facial expressions (hypomimia)

Question 8

Aside from the classic triad what other symptoms are seen in Parkinson’s? (5)

Answer 8

○ Depression
○ Sleep disturbance and insomnia
○ Loss of the sense of smell (anosmia)
○ Postural instability (increasing the risk of falls)
Cognitive impairment and memory problems

Question 9

What is multiple system atrophy?

Answer 9

A Parkinson plus syndrome
Neurones in the brain degenerate
Leads to Parkinson’s presentation and also autonomic dysfunction (causing postural hypotension, constipation, abnormal sweating and sexual dysfunction) and cerebellar dysfunction (causing ataxia).

Question 10

Aside from Parkinsonian symptoms what are some other symptoms of dementia with Lewy bodies?

Answer 10

visual hallucinations, delusions, REM sleep disorders and fluctuating consciousness.

Question 11

What are some Parkinson plus syndromes? (4)

Answer 11

Multiple system atrophy
Dementia with Lewy bodies
Progressive supranuclear palsy
Corticobasal degeneration

Question 12

What are the management options of Parkinson’s? (4)

Answer 12

• Levodopa (combined with peripheral decarboxylase inhibitors)
• COMT inhibitors
• Dopamine agonists
• Monoamine oxidase-B inhibitors

Question 13

What is drug type is levodopa often combined with to stop it metabolising?

Answer 13

Peripheral decarboxylase inhibitor

Question 14

Name 2 peripheral decarboxylase inhibitors

Answer 14

Carbidopa
Benserazide

Question 15

What is the action of peripheral decarboxylase inhibitors?

Answer 15

Stops levodopa being metabolised in the body before it reaches the brain

Question 16

Name 2 combination drugs of levodopa with a peripheral decarboxylase inhibitor

Answer 16

○ Co-beneldopa (levodopa and benserazide), with the trade name Madopa
○ Co-careldopa (levodopa and carbidopa), with the trade name Sinemet

Question 17

What is a major side effect of levodopa?

Answer 17

Dyskinesia e.g.
§ Dystonia (where excessive muscle contraction leads to abnormal postures or exaggerated movements)
§ Chorea (abnormal involuntary movements that can be jerking and random)
§ Athetosis (involuntary twisting or writhing movements, usually in the fingers, hands or feet)

Question 18

What drug can manage dyskinesia associated with levodopa? What is its mechanism?

Answer 18

Amantadine
Glutamate antagonist

Question 19

Name a comt inhibitor

Answer 19

Entacapone

Question 20

What is the action of comt inhibitors?

Answer 20

Stop the metabolism of levodopa in both the brain and body

Question 21

What is a main side effect of dopamine agonists?

Answer 21

Pulmonary fibrosis

Question 22

Name 3 dopamine agonists

Answer 22

□ Bromocriptine
□ Pergolide
□ Cabergoline

Question 23

What is the action of monoamine oxidase-B inhibitors?

Answer 23

Blocks mao-b enzymes .: increases circulating dopamine

Question 24

Name 2 monoamine oxidase-B inhibitors

Answer 24

® Selegiline
® Rasagiline