parkinson's disease

Question 1

what is PD? motor & non-motor symptoms

Answer 1

PD - progressive neurodegenerative condition
- results from death of dopaminergic cells of substantia nigra in brain

motor symptoms - hypokinesia, bradykinesia, rest tremor, postural instability

non-motor symptoms - dementia, depression, sleep disturbance, bowel dysfunction, speech and language issues

when PD diagnosis confirmed - advised to inform DVLA and car insurer

alleviated by increasing dopamine

Question 2

what is the drug treatment?

Answer 2

motor symptoms that decrease qol:
- levodopa + carbidopa/benserazide

motor symptoms that don’t affect qol:
- levodopa
- non-ergot derived dopamine receptor agonists
- monoamine oxidase B inihibitors

Question 3

levodopa imp points

Answer 3

levodopa by itself - only 1% absorbed (10% crosses BBB, 10% of the 10% is absorbed)

carbidopa/benserazide (co-careldopa/co-beneldopa) added to prevent breakdown of levodopa before entering brain

adverse effects:
- pathological gambling
- binge eating
- hypersexuality

sudden onset sleepiness - treat with modafinil

RED URINE

Question 4

non ergot dopamine receptor agonists - imp points

Answer 4

pramipexole, ropinirole, rotigotine

impulse disorders, sudden onset of sleep - more likely with non ergot

hypotension

Question 5

MAO-B inhibitors imp points

Answer 5

rasigiline, selegiline

• cause hypertensive crisis when given with pseudoehpedrine or phenylephrine

Question 6

adjuvant therapy?

Answer 6

if pt gets - dyskinesia, motor fluctuations despite optimal levodopa therapy
+ non ergot, MAO-B inhibitors
or COMT inhibitors (tolcapone, entacapone)

use ergot derived dopamine agonist (bromocriptine, cabergoline) if symptoms not controlled with non ergot

if dyskinesia still not adequately managed - CONSIDER AMANTADINE

Question 7

COMT inhibitors imp points

Answer 7

entacapone - red brown urine

tolcapone - hepatotoxic

increases sympathetic side effects - avoid in CVD

Question 8

what to do in patients with “off periods”

Answer 8

off periods occur due to dose deterioration - use MR preparations

Question 9

how to treat nocturnal akinesia + postural hypotension

Answer 9

nocturnal akinesia - treat with levodopa + dopamine agonists as 1st line
rotigotine 2nd line

postural hypotension - midodrine