T3-Parkinson's Disease Medications-MJ Flashcards
What are the cardinal symptoms of Parkinson’s?
Tremor
Rigidity
Postural instability
Slowed movements
Tremor, rigidity, postural instability, and slowed movements are all motor muscular symptoms of Parkinson’s. What are some “other symptoms”?
Depression
Psychosis
Eventually leads to dementia
What does Parkinson’s disease eventually lead to?
Dementia
What are the 5 early symptoms of Parkinson’s?
Decreased smell Increase salivation Clumsiness of hands Micrographia Decrease voice volume
What is micrographia?
Small handwriting
What is the pathophysiology of Parkinson’s?
The substantia nigra (black substance) is part of the EPS. The substantia nigra is the part that is broken. Neurons from this region release DOPAMINE to another part. So when the substantia nigra is broken/dying, there is DECREASED dopamine and INCREASE acetycholine
What are possible treatment options for Parkinson’s?
Increase dopamine
Decrease Ach levels
Or try doing both
What are some of the challenges when trying to treat Parkinson’s?
“off times”
Drug-induced dyskinesias (ticks)
Loss of effect (the wear off)
What does “off time” mean when referring to Parkinson’s treatment?
The drug randomly stops working for a period of time
What are the major drug classes for Parkinson’s?
Levodopa/carbidopa
Dopamine agonists
MOA-B inhibitors
Why can’t we just give dopamine to the patient with Parkinson’s when that is all they need?
Dopamine can’t cross BBB easily, and even if it could it has a short half life!
Does dopamine cross BBB easily?
No
Does dopamine have a long or short half life?
Short
Levodopa: Can this drug cross the BBB?
Yes!
Levodopa: What happens when levodopa crosses the BBB into the CNS?
Levodopa is accepted into dopaminergic receptors where it gets converted into dopamine
Why do we have to add Carbidopa with levodopa?
Once levodopa is converted to dopamine, it can spread into the periphery. Adding carbidopa allows this to not happen as much. This keeps the dopamine in the brain (where we want it), which allows us to decrease the dose, which in turn, decreases the side-effects (cardiovascular)
How effective is the levodopa/carbidopa combo?
VERY; there is a 50% reduction in Parkinson’s symptoms