Parkinson's disease Flashcards
What is the pathophysiology of parkinson’s disease?
Progressive reduction of dopamine production in the basal ganglia of the brain - causing a movement disorder.
What is the classic triad of parkinson’s disease presentation?
- resting tremor
- rigidity of movement (leadpipe)
- bradykinesia (slowness of movements)
This are typically assymetrical.
Describe the features of a parkinson’s tremor?
- 4-6hz frequency (meaning it happens 4-6 times a second)
- describes are ‘pill rolling’
- more pronounced when resting
- improves on voluntary movement
- worse when the patient is distracted
How is the rigidity in parkinson’s disease described?
- cogwheel like rigidity
- resistance to passive movement of a joint
- upon arm movement - you feel a tension that gives way in small little jerk movements
Describe the bradykinesia features in parkinson’s disease?
- slower, smaller movements
- shuffling gait with a reduced arm swing
- difficulty initiating movements - e.g. standing still to walking
- reduced facial movements and expressions (hypomima)
Describe the gait seen in parkinson’s disease?
- shuffling gait
- reduced arm swing
What features (outside of the classic triad) may be seen in parkinson’s disease?
- depression
- cognitive impairment and memory problems
- sleep disturbance and insomnia
- postural instability - stopped with a forward tilt
How is parkinson’s disease managed?
Medications such as
- levodopa (synthetic dopamine)
- COMT inhibitors - e.g. entacapone
- dopamine agonsts - bromocryptine
- monoamine oxidase B inhibitors - rasagiline
What happens over time as co-careldopa is used to treat parkinson’s disease?
It’s effectiveness decreases over time ( complete loss is often after 2-5years)
Why is levodopa given as co-careldopa?
Levodopa is combined with carbidopa to prevent early breakdown of dopamine ( stops breakdown in the peripheral NS so that it enters the central nervous system)
How do COMT inhibitors work for parkinson’s disease?
Inhibits the COMT enzyme - which normally metabolises levodopa. Hence slows the breakdown of levodopa.
What class of drug is entacapone?
COMT inhibitor
What condition can be managed with co-careldopa, entacapone, bromocryptine or rasagiline?
Parkinson’s disease
What is entacapone used to manage?
Parkinsons disease
What class of medication is bromocryptine?
dopamine agonist
What is the main side effect of dopamine agonists?
Pulmonary fibrosis
What class of medication is rasagiline?
Monoamine oxidase-B inhibitor
How do Monoamine oxidase-B inhibitors work to manage parkinson’s disease?
Stops the breakdown of dopamine
