Parkinson's Flashcards
What is the simple pathophysiology of Parkinsons?
Progressive reduction of Dopamine in Basal Ganglia –> movement disorders
Where in the Basal Ganglia is Dopamine produced?
Substantia nigra
Are the symptoms of Parkinsons symmetrical or asymmetrical?
Asymmetrical
What are the classic of Parkinsons symptoms? (4 things)
- Tremor
- Rigidity
- Akinesia
- Postural instability
TRAP
Who is the typical person to have Parkinsons?
70 year old Man
aka Mohammed Ali RIP
When is the Tremor better / worse in Parkinsons?
- Better @ voluntary movement
- Worse @ distracted
What is the Rigidity in Parkinsons reffered to?
Cogwheel rigidity
How do you see Cogwheel rigidity @ examination? (2 steps)
- Passively flex + extend pt arm
- Arm gives way in small increments (little jerks)
What does Akinesia / Bradykinesia in Parkinsons refer to?
Movements get Smaller + Slower
How does Bradykinesia present in Parkinsons? (4 things)
- Handwriting gets smaller (classic exam q)
- Can only take small steps (everyday im shuffling)
- Difficulty initiating movement (standing à walking)
- Reduced facial expressions (hypomimia)
What are the differences between Parkinsons Tremor vs Benign Essential Tremor? (4 things)
- Parkinsons: Asymmetrical // BET: Symmetrical
- Parkinsons: 4-6 per second // BET: 5-8
- Parkinsons: Worse @ rest // BET: Better @ rest
- Parkinsons: Presents w other symptoms // BET: N/A
How is the Dx of Parkinsons made?
Clinically
What does NICE guidelines recommend using to Dx Parkinsons?
UK Parkinsons Disease Society Brain Bank Clinical Diagnostic Criteria
Is there a cure for Parkinsons?
No :(
What is the aim of Mx of Parkinsons? (2 things)
- Control symptoms
- Minimise side fx
What are the medications available for Parkinsons Mx?
- Levodopa
- COMT inhibitors
- Dopamine agonists
- Monoamine Oxidase B inhibitors
What is Levodopa?
Synthetic dopamine to boost dopamine levels
What is Levodopa often given with?
Peripheral Decarboxylase Inhibitors (e.g Carbidopa)
What is the point of Peripheral Decarboxylase Inhibitors (e.g Carbidopa)?
Stops Levodopa being broken down peripherally b4 reaches brain
Even though Levodopa is the most effective Parkinsons meds, why is it reserved and for who?
Reserved bc becomes less effective over time
Reserved for when other meds aren’t controlling symptoms properly
What is the main Side effect of too much Dopamine?
Dyskinesias (aka excessive motor activity)
What are examples of Dyskinesias? (3 things)
- Dystonia
- Chorea
- Athetosis
What is Dystonia?
Excessive muscle contraction –> abn postures / exagg movements
What is Chorea?
Abn invol movements (e.g jerking)
What is Athetosis?
Invol twisting / writhing movements (usually in fingers / feet)
What is an example of a COMT inhibitor?
Entacapone
How do COMT inhibitors (e.g Entacapone) work? (3 steps)
- COMT Enzyme metabolises Levodopa in Body + Brain
- COMT Inhibitor slows this down
- Extends effective duration of Levodopa
What do Dopamine Agonists do?
Mimic dopamine –> stimulate dopamine receptors
What is the point of Dopamine Agonists? (2 things)
- To delay use of Levodopa
- To reduce dose of Levodopa needed to control symptoms
What is a Side fx of prolonged use of Dopamine Agonists?
Pulmonary Fibrosis
What are examples of Dopamine Agonists? (2 things)
- Bromocryptine
- Cabergoline
What is an example of a Monoamine Oxidase B inhibitor?
Rasagiline
How do Monoamine Oxidase B inhibitors (e.g Rasagiline) work? (3 steps)
- Monoamine Oxidase B Enzyme metabolises Dopamine
- Monoamine Oxidase B Inhibitor slows this down
- Delays use of Levodopa + Reduces required dose of Levodopa when it’s used
