Parkinson's Disease

Question 1

what is parkinsons

Answer 1

a progressive, degenerative disorder of the basal ganglia function
- characterized by tremor, rigidity, bradykinesia

Question 2

what is the basal ganglia

Answer 2

function of the cerebellum to make smooth coordinated movements
- part of the basal ganglia is the substantia nigra where dopamine is produced

Question 3

what is primary parkinson’s disease

Answer 3

idiopathic
- genetic and sporadic
* damage to dopamine producing cells*

Question 4

what is secondary parkinson’s

Answer 4

acquired
- infection
- intoxication
- trauma
- drug induced (antiemetics/depressions will interfere with dopamine transmission)
alter production of dopamine

Question 5

what are the risk factors for parkinson’s

Answer 5

age (70s)
more likely men
genetics
anxiety/depression
head trauma
hysterectomy
coffee consumption (protective)

Question 6

what is dopamine

Answer 6

NT that is both inhibitory and excitatory
- in parkinson’s it is inhibitory
- helps muscles work smoothly, controllably, and without unwanted movements
* inhibits unnecessary movement

Question 7

what is ACh

Answer 7

an excitatory NT that works in conjunction with the dopamine system
- prevents unwanted movements
- must be balanced, if one goes up then one must come down

Question 8

what is the pathogenesis of parkinson’s

Answer 8

• destruction of substantia nigra in basal ganglia
• dec levels in dopamine
• imbalance between dopamine and ACh
• relative excess of ACh
• loss of controlled movements and balance

Question 9

what are the clinical manifestations

Answer 9

• bradykinesia (slowness of movements)
• cog wheel rigidity (stiffness)
• resting tremor
• shuffling gait
• mask like expression
• postural instability
  *gradual onset and progression, typically one side of body first *

Question 10

what is the classic triad of manifestations of parkinson’s

Answer 10

tremor
rigidity
bradykinesia

Question 11

what are the characteristics of tremors in parkinson’s

Answer 11

• often first sign
• affects handwriting
• more prominent at rest
• aggravated by stress or concentration
• pill roll

Question 12

what are the two types of tremors

Answer 12

parkinsons
essential

Question 13

what is an essential tremor

Answer 13

results form faulty neurological impulses w fine motor movements
- occur with motor function
- no other sx of parkinsons

Question 14

what is the parkinson’s tremor

Answer 14

results from a dopamine def
- occur with rest and improve with movements
- other symptoms of parkinsons

Question 15

what is rigidity

Answer 15

resistance to passive movements
- cog wheel rigidity –> movements are jerky and slow
- sustained muscle contractions
- too much ACh
- associated complaints are muscle soreness, aches, pain

Question 16

what is bradykinesia

Answer 16

loss of automatic movements
- no blinks, swinging of arms, swallowing saliva, no self expression with hands and face
–> results in drooling, flat face
overall lack of spontaneous movement

Question 17

what are complications of parkinson’s

Answer 17

dementia
depression/anxiety
decreased mobility –> malnutrition, aspiration, pneumonia, UTIs, skin breakdown
drug related complications

Question 18

what are the goals of pharm of parkinsons

Answer 18

maintain independence and dec sx that are associated

Question 19

how do parkinson’s drug work

Answer 19

correct the imbalance btw dopamine and ACh
- enhance dopamine (dopaminergic) or block ACh (anticholinergic)

Question 20

what is levodopa/carbidopa

Answer 20

most effective drug for parkinson’s that is a combo drug

Question 21

what is the moa of levodopa

Answer 21

converts dopamine in the brain and activates dopamine receptors

Question 22

what is the moa of carbidopa

Answer 22

blocks destruction of levodopa

Question 23

what is the disadvantage of levodopa/carbidopa

Answer 23

takes several months to see improvement
does not work long term
- dose eventually wears off so may need shorter dose intervals
- abrupt loss of effect calles the on off phenomenon that can occur at anytime (off periods will inc over time) (can be reduced w drugs and avoid high protein meals)

Question 24

what are the adverse effects of levadopa

Answer 24

N/V (give low doses, take w food)
dyskinesias (range from annoying to disabling)
postural hypotension
dysrhythmias
psychosis: hallucinations, nightmares, paranoia
darken sweat and urine
activate malignant melanoma

Question 25

what interactions dec levodopa

Answer 25

vit B6
antipsychotics
protein

Question 26

what interactions inc levodopa

Answer 26

carbidopa
anticholinergics
MAOi –> can cause toxicity

Question 27

what is a duopa

Answer 27

carbidopa-levodopa infusion that can be
- instilled into a feeding tube into the small intestine
- gel form suspension
- continuous infusion for continuous blood levels up to 16 hrs/day

Question 28

why is dopa used

Answer 28

for pts who respond to drugs but response fluctuates
- more consistent levels of drug in the body

Question 29

what is important info to know about duopa

Answer 29

major drug interactions
- anti htn
- mao i
- antipsychotic
- metoclopramide
- isoniazid
- iron
- vitamins (B6)
- high protein

Question 30

what are the side effects of duopa

Answer 30

• falling asleep without warning
• orthostatic hypotension
• hallucinations
• unusual urges
• depression
• dyskinesia
• side effects related to placement of tube (infection, dislodge)*

Question 31

what is the class of pramipexole

Answer 31

dopamine receptor agonist

Question 32

what is the moa of pramipexole

Answer 32

binds with D2 receptors –> stimulates dopamine receptors

Question 33

what are the indication for pramipexole

Answer 33

mono therapy in early PD (younger pts)
combined with carbidopa-levodopa in advanced PD
restless leg syndrome (inhibits dopamine receptors to block sensation)

Question 34

what are the side effects of pramipexole

Answer 34

N
sleep attacks
pathologic gambling and other compulsive behaviors
when combined with levodopa
- orthostatic hypotension.
- dyskinesia
- hallucination risk doubles

Question 35

what is the class of ropinirole

Answer 35

dopamine receptor agonist –>idiopathic PD

Question 36

what is the moa of ropinirole

Answer 36

unknown
- thought to inc nerve impulses within the substantia nigra

Question 37

what are the effects of ropinirole

Answer 37

adverse effects similar to PD drugs
- long term use may be inc risk of DM and acromegaly

Question 38

what are other dopamine agonists

Answer 38

ritgotine: daily patch
apomorphine: short acting sub q for fast relief of sx used in the “off” phase