Parkinson's Disease

Question 1

What is Parkinson’s

Answer 1

dopaminergic deficiency and relative cholinergic excess in the brain; drugs act by increasing dopamine or acting as dopamine agonists or as anticholinergics.

Question 2

Drugs used to treat parkinsons

Answer 2

1. Levodopa OR dopamine agonist
2. Rotigotine (good for oral difficulties)
3. Anticholinergics (used infrequently)

Question 3

Rationale for drug use
Parkinson’s

Answer 3

Provide symptomatic relief.

Question 4

Clinical signs and symptoms
Parkison’s

Answer 4

• Bradykinesia
• Rest tremor
• Rigidity
• Loss of postural reflexes

Question 5

Indications
Levodopa

Answer 5

Early and advanced Parkinson’s (PD)
First line treatment for most people

Question 6

MOA
Levodopa

Answer 6

Artifical dopamine, levodopa breaksdown into dopamine. Parkinsons is lack of dopamine

Question 7

Adverse reactions
Levodopa

Answer 7

• Nausea and vomiting
• Postural hypotension
• Cardiac arrhythmias
• Constipation
• Sudden sleep episodes
• Impulse control disorders
• confusion, hallucinations

Question 8

Drug interactions
Levodopa

Answer 8

• Dopamine antagonists decrease its therapeutic effects – e.g. antipsychotics
• Drugs with dopamine agonist activity may increase the adverse effects of levodopa
• Administration of levodopa with drugs to lower BP may result in an additional drop in BP – e.g. methyldopa
• Antinausea medications (e.g. metoclopramide, prochlorperazine)
• Antipsychotic medications (e.g. haloperidol, risperidone)

Question 9

Practice points
Levodopa

Answer 9

Levodopa preferred in >70yrs

Question 10

Generic drug names
Dopamine agonists

Answer 10

bromocriptine
Rotigotine - available in patch for pts w/ oral difficulty (can combine with levodopa)
Apomorphine - used in cases of severe motor dysfunction (causes severe nausea)

Question 11

Indication
Dopamine agonists

Answer 11

Parkinson’s Disease

Question 12

MOA
Dopamine agonists

Answer 12

Mimic the actions of dopamine in the body to relieve symptoms related to low levels of dopamine

Question 13

Contraindications
Dopamine agonists

Answer 13

Pregnancy
nursing mothers

Question 14

Adverse reactions
Dopamine agonists

Answer 14

Impulse control disorders, hypersexuality and neuropsychiatric effects

Cabergoline, bromocriptine and pergolide
* side effects similar to levodopa plus cardiac valvular disease and pleuro pulmonary retroperitoneal fibrosis

Pramipexole, rotigotine, ropinirole
* side effects similar to levodopa plus peripheral oedema

Question 15

Drug interactions
Dopamine agonists

Answer 15

• Antinausea medications (e.g. metoclopramide, prochlorperazine)
• Antipsychotic medications (e.g. haloperidol, risperidone)

Question 16

Practice points
Dopamine agonists

Answer 16

• Dopamine agonists are generally preferred in younger patients
• Cabergoline, bromocriptine and pergolide
• Monitoring essential (interval echocardiograms, respiratory function and chest X-ray) for those unable to switch from ergot preparations
• Efficacy and safety of the oral dopamine agonists similar
• Pergolide is marketed for use as an adjunct to levodopa only - Bromocriptine and pergolide rarely used