Parkinson's disease Flashcards
What is the pathophysiology
Progressive reduction in dopamine in the basal ganglia
wHAT are the three classic features?
- Resting tremor
- Rigidity
- Bradykinesia
Explain the characteristics of the tremor
Worse on one side
4-6 hertz frequency
Pill rolling tremor
Worse on resting
Explain the nature of the rigidity
Passive rigidity
Cogwheel
Explain the features due to bradykinesia
Micrograpia
Shuffling gait
Festinating gait
Difficulty initiating movement
Difficulty turning around
Hypomimia - reduced facial movements and expression
What are the other features of parkinsons
depression
insomnia
anosmia
postural instability
cognitive impairment
What are Parkinson’s plus syndromes?
Multiple system atrophy
Lewy body dementia
Progressive supra nuclear palsy
Corticobasal degeneration
How is it diagnosed?
Clinically
What are treatment options?
Levodopa
COMT
Dopamine agonists
Monoamine oxidase-B inhibitors
What is the most effective treatment?Why isn’t this the first line?
Levodopa
Effective but becomes less effective over time
What is levodopa usually combined with?Why?
Peripheral decarboxylase inhibitor - e.g. carbidopa, benserazide
Stops levodopa from being metabolised in the body before it reaches the brain
What is the main side effect of levodopa?
Give examples
Dyskinesia:
Dystonia
Chorea
Athetosis - involuntary twisting or writhing movements
What can be given to manage dyskinesia associated with levodopa?
amantadine
How do COMT inhibitors work/
COMT enzyme metabolises levodopa in both the body and brain. Entacapone is taken with levodopa (and a decarboxylase inhibitor) to slow the breakdown of the levodopa in the brain.
Therefore extends the effective duration of the levodopa
What are examples of dopamine agonists
bromocriptine
cabergoline
