Parkinson's treatment

Question 1

When should drug treatment for PD commence?

Answer 1

When symptoms become disabling

Question 2

Examples of dopamine receptor agonists (3)

Answer 2

Bromocriptine
Cabergoline
Ropinorole

Question 3

Side-effects/risks of dopamine receptor agonists (3)

Answer 3

Impulse control disorders
Excessive daytime somnolence
Cardiac/pulmonary/retroperitoneal fibrosis

Question 4

What two classes of drug is levodopa often combined with, give an example and state their mechanism of action?

Answer 4

Decarboxylase inhibitor e.g. carbidopa, to reduce peripheral metabolism of dopamine.
COMT inhibitor e.g. entacapone- inhibit dopamine breakdown, help counter the end of dose effect

Question 5

What is the on-off effect sometimes seen with levodopa?

Answer 5

Sudden, sometimes unpredictable changes in symptoms from well-controlled to badly controlled

Question 6

Unwanted effects of levodopa (5)

Answer 6

Reduced effectiveness with time
Dyskinesia
On-off effect
Dry mouth
Palpitations

Question 7

Selegiline is an example of…

Answer 7

Monoamine oxidase B inhibitor

Question 8

What does selegiline do?

Answer 8

Inhibits breakdown of dopamine secreted by dopaminergic neurones

Question 9

How is amantadine thought to work?

Answer 9

Increases dopamine release and inhibits synaptic re-uptake

Question 10

What is the preferred anti-emetic for patients with PD, and why?

Answer 10

Domperidone. Other anti-emetics are dopamine antagonists which cross the blood brain barrier, domperidone does not

Question 11

Madopar (levodopa) may cause what side effect?

Answer 11

Orthostatic hypotension