Parkinson's Disease Management

Question 1

What is first line treatment if motor symptoms are affecting patients QOL

Answer 1

Levodopa

Question 2

What are first line treatments if motor symptoms are not affecting QOL

Answer 2

Dopamine agonist
Levodopa
MAO-B inhibitors

Question 3

When should treatment be started? Why

Answer 3

Later on if possible or when PD seriously interferes with life
Efficacy of levodopa reduces with time requiring larger and more frequent dosing with worsening SE and response fluctuations.

Question 4

What is Levopdopa? How is it given? ADRs?

Answer 4

Dopamine precursor
Given with dopa-decarboxylase inhibitor in co-careldopa to prevent peripheral metabolism of levodopa to dopamine
ADRs: dyskinesias (involuntary writhing movement), painful dystonia, psychosis, visual hallucinations, NV (give domperidone), on-off effect (fluctuation), dry mouth
No use in neuroleptic induced parkinsonism

Question 5

Dopamina agonist
examples
ADRs

Answer 5

Bromocriptine, cabergoline, ropinirole, pramipexole, apomorphine

Can be used to delay starting levodopa or allow for lower doses of levodopa

Ergot derived dopamine agonists (bromocriptine, cabergoline) are associated with pulmonary, retroperitoneal and cardiac fibrosis

ADRs:
Drowsiness - excessive daytime somnolence
Nausea
Impulse control disorders (gambling, hyper sexuality)
Hallucinations

Question 6

What must be done prior to treatment with bromocriptine

Answer 6

Ergot derived dopamine agonists (bromocriptine, cabergoline) are associated with pulmonary, retroperitoneal and cardiac fibrosis

Do echo, ESR, creatinine and CXR prior to treatment and monitor closely

Question 7

What is amantadine? What is it used for?

Answer 7

NMDA receptor antagonist - blocks dopamine reuptake

The specific symptoms targeted by amatadine therapy are dyskinesia and rigidity

Question 8

What is apomorphine?

Answer 8

Potent dopamine agonist used with continuous SC infusion to even out end-of dose affects or as rescue for sudden ‘off’ freezing in levodopa

Question 9

What are MAO-B inhibitors, example? Function? ADRs?

Answer 9

Selagiline, rasagiline
Alternative to dopamine agonist in early PD
Inhibits breakdown of dopamine secreted by dopaminergic neurones

SE: postural hypotension, AF

Question 10

COMT inhibitor examples? Function?

Answer 10

Entacapone, tolcapone
May help motor complications in late disease
Lessen the ‘off’ time in those with end-of-dose wearing off.
COMT is an enzyme involved in the breakdown of dopamine
Used in conjunction with levodopa

Tolcapone may cause hepatic complications

Question 11

Antimuscarinics examples, use, side effects

Answer 11

Procycllidine, benzhexol, orphenadrine, benzotropine
Used to treat drug induced parkinsonism rather than IPD
Help tremor and rigidity
Limit to young patients
Multiple side effects
Dry mouth, blurred vision, urinary retention, constipation

Question 12

Why must you be careful on withdrawing medication in PD

Answer 12

Risk of acute akinesia or neuroleptic malignant syndrome

Also if drug is not absorbed due to gastroenteritis or not taken - advise patients

Question 13

What can be used if there is orthostatic hypotension?

Answer 13

Midodrine

Acts on peripheral alpha receptors to increase arterial resitance

Question 14

What is Wilson’s disease?

Answer 14

Autosomal recessive disorder of copper excretion with excess deposition in liver and CNS - basal ganglia
Liver disease, parkinsonism, depression, reduced cognition, kayser-fleischer rings - copper in iris

Test: urine 24h copper excretion is high

Diet: avoid foods with high copper, liver, chocolate, nuts, mushrooms
Check water sources
Lifelong penicillamine
Monitor
Liver transplant if severe liver disease