CNS 2 Part 1 Flashcards
(41 cards)
What is the 2nd most common neurodegenerative disease?
Parkinson’s Disease
Which sex has a greater incidence of parkinson’s?
Men
How do the motor features of Parkinson’s appear?
Typically start insidiously and emerge slowly over weeks or months
What are not non-motor symptoms of Parkinson’s?
Depression, dementia, and hallucinations as well as autonomic, sensory, and REM sleep behavior disorders
What are the two major neuropathologic findings of Parkinson’s?
Loss of pigmented dopaminergic neurons in the substantia nigra pars compacta and the presence of Lewy bodies in the substantia nigra
Approximately how many of dopaminergic neurons are lost before the motor signs of Parkinson’s disease emergy?
60-80%
What is the overall goal of medical managment of Parkinson disease?
Control signs and symptoms for as long as possible while minimizing adverse effects
What are the six main categories of pharmacologic treatment for parkinson’s disease?
Levodopa
Monoamine Oxidase- B inhibitors
Dopamine receptor agonists
Catechol-O- Methyl transferase inhibitory
Amantadine
Anticholinergic
Why is Levodopa rarely used alone?
rarely used alone due to low bioavailability from a large first pass effect and significant adverse effects of nausea, anorexia, psychoses, and dyskinesias
What are the pharmacodynamics of levodopa?
are that in restores the synaptic concentrations of dopamine by activating the post-synaptic dopamine receptors
What is the wearing off and on off phenomenon associated with levodopa?
refers to a decrease in effectiveness at the of the drug’s dosing cycle resulting in periods of akinesia (no movement) or dyskinesia (unpredictable episodes of random movement) that occur with this drug
How can the wearing off and on off phenomenon be avoided in levodopa?
Improved with adding dopamine receptor agonist
What are the Monoamine oxidase (MAO)-B inhibitors drugs?
Rasagiline, selegiline, and safinamide
When do MAO-B Inhibitors provide symptomatic benefit?
When used as monotherapy or as adjuncts to levodopa in early disease or in patient experiencing motor fluctuations
How do MAO-B inhibitors work?
They inhibit the activity of MAO-B oxidases that are responsible for inactivating dopamine
What are the adverse effects associated with MAO-B inhibitors?
extrapyramidal effects, insomnia, orthostatic hypotension, malignant hyperthermia if administered with meperidine, and hypertensive crisis.
Nausea and headache are the most common side effects associated with all the MAO-inhibitors.
What are the two main types of Dopamine Receptor Agonists?
Ergot or non ergot derived
How do Dopamine Receptor Agonists work?
exert their pharmacologic effect by directly activating dopamine receptors, bypassing the presynaptic synthesis of dopamine by the neurons in the substantia nigra
What was the first dopamine receptor agonist to be developed?
Bromocriptine
Which Dopamine Receptor Agonist is used as a rescue drug in patients experiencing sudden akinetic episodes that has more severe side effects?
Apomorphine
Side effects are: dyskinesias, drowsiness, sweating, hypotension)
What are the adverse effects of Dopamine Receptor Agonists?
The main categories of adverse effects from the dopamine receptor agonists are GI, cardiovascular, dyskinesias similar as to occur with L-dopa, and mental disturbances including problems with impulse control resulting in compulsive gambling, shopping, betting, sexual activity, etc
Which patients are ergot-derivatives are avoided in?
Patients with peripheral vascular disease
What are the contraindications of dopamine agonists?
Psychotic illness or recent MI
What are the main Catechol-O-Methyl Transferase Inhibitors (COMT-Inhibitors) drugs?
Tolcapone, entacapone, opicapone
