CHAPTER 4: CNS: Parkinson's Disease

Question 1

Which neurotransmitter is deficient in Parksinson’s Disease?

Answer 1

Dopamine

Question 2

Does drug therapy prevent disease progression?

Answer 2

No - improves quality of life

Question 3

Who should patient with suspected Parksinson’s Disease be referred to?

Answer 3

A specialist to confirm the diagnosis

Question 4

How often should patients with Parksinson’s Disease be reviewed?

Answer 4

Every 6-12 months

Question 5

What percentage of people with Parksinson’s Disease will respond poorly to treatment?

Answer 5

5-10%

Question 6

Which classes of drug are initially used to treat Parksinson’s Disease? (3)

Answer 6

1. Dopamine agonists (non-ergot)
2. Levodopa
3. MAOB inhbitors

Question 7

Give 3 examples of dopamine agonists

Answer 7

1. Pramipexol
2. Ropinirole
3. Rotigotine

Question 8

Why are the ergot-derived dopamine agonists (bromocriptine, carbegoline and pergolide) now rarely used?

Answer 8

Risk of fibrotic reactions

Question 9

Dopamine agonists cause fewer what than levodopa?

Answer 9

Motor complications

Question 10

Dopamine agonists cause more what compared with levodopa?

Answer 10

Psychiatric side effects

Question 11

Which dopamine agonist is used in advanced disease for patients experiencing unpredictable “off” periods with levodopa?

Answer 11

Apomorphine

Question 12

Can a GP initiate apomorphine?

Answer 12

No - specialist initiation only

Question 13

How is the threshold for apomorphine determined?

Answer 13

After an overnight period without antiparkinson’s medicines to induce an “off” episode

Question 14

How is apomorphine admnistered?

Answer 14

Via subcutaneous injection in the lower abdomen or outer thigh

Question 15

What is levodopa always given with?

Answer 15

An extracerebral dopa-decarboxylate inhibitor

Question 16

A dopa-decarboxylate inhibitor is used to prevent symptoms of peripheral conversion of the administered levodopa to dopamine to prevent which side effects? (3)

Answer 16

1. Nausea
2. Vomiting
3. Cardiovascular

Question 17

Which 2 peripheral dopa-decarboxylate inhibitors are given with levodopa?

Answer 17

1. Carbidopa

2. Benserazide

Question 18

How should levodopa be introduced to patients?

Answer 18

At low doses then titrated up in small steps

Question 19

Which antiemetic can be given to control side effects of nausea and vomiting?

Answer 19

Domeperidone

Question 20

Which complications can occur with treatment with levodopa?

Answer 20

Motor

Question 21

What occurs during the “on” period with levodopa treatment?

Answer 21

Normal function

Question 22

What occurs during the “off” period with levodopa treatment?

Answer 22

Weakness and restricted mobility

Question 23

On and off symptoms of levodopa are associated with response fluctuations and what do they eventually lead to?

Answer 23

End of dose fading with progressively shorter duration of benefit

Question 24

Give 2 examples of MAOB inhibitor

Answer 24

1. Selegiline

2. Rasagiline

Question 25

Which antimuscarinic drug can be used to treat parkinson side effects of antipsychotics?

Answer 25

Procyclidine

Question 26

What side effect of both dopamine agonists and levodopa should patients and carers be counselled on?

Answer 26

Impulse control disorders

Question 27

As well as impulse control disorders, what else should patients be counselled on with dopamine agonist? (2)

Answer 27

1. Sudden onset of sleep | 2. Hypotensive reactions