anti parkinson drugs Flashcards
neurologic functions and neurotransmission
one CNS function can be regulated by multiple neurotransmitters
one neurotransmitter could affect many CNS functions.
the interactions among neurotransmitters
it is impossible to interfere with one neurotransmitter without affecting the other neurotransmitters
what is parkinsons disease?
loss of dopamine. degeneration of dopamine secreting neurons in substantia nigra. the cause is unknown and their is no cure available.
dec neurons–>dec Dopamine secretion–>dec motor control—>movement disorder
levodopa
L-DOPA. can cross the blood brain barrier and is converted into dopamine in the CNS. most commonly prescribed.
not only do we give them levodopa, but we also give them carbidopa (bodygauard)
cant give dopamine directly because cant cross the BBB
carbidopa
can not cross BBB. prevents peripheral conversion fo L-DOPA into dopamine. makes sure that more L-DOPA delivered into the CNS.
pramipexole
dopamine receptor agonsit. bind and activate dopamine receptors. can not be broken down by COMT, and MAO-B.
Non ergot.
Side effects: drowsiness, nausea, vomiting, dry mouth,
dizziness, leg swelling, and orthostatic hypotension
Impulse control disorders: gambling, shopping, binge
eating, and sexual behavior (overactive DA signaling)
ropinirole
dopamine receptor agonsit. bind and activate dopamine receptors. can not be broken down by COMT, and MAO-B.
Non ergot.
Side effects: drowsiness, nausea, vomiting, dry mouth,
dizziness, leg swelling, and orthostatic hypotension
Impulse control disorders: gambling, shopping, binge
eating, and sexual behavior (overactive DA signaling)
selegiline
prevent Dopamine breakdown
Monomamine oxidase type B (MAO-B) inhibitors
tolcapone
prevent dopamine breakdown
catechol-o-methyltransferase (COMT) inhibtiors
peripheral and central
amantadine
unknown mechanism.
antiviral medication to treat flu.
increase dopamine release from presynaptic neuron, decrease dopamine reuptake.
side effects: ataxia and livedo reticularis.
benztropine
(m1) antangonist. antimuscarinic.
decreases cholinergic signaling and inhibits the reuptake of dopamine thus reduced motor symptoms like tremors.
normal chemical balance vs chemical imbalance
in a normal brain, the levels of dopamine and acetylcholine are evenly balanced.
in parkinsons disease, the levels of dopamine are reduced and acetylcholine is relatively overactive (movement disorder)
muscarinic receptors and parkinsons disease
inhibiting muscarinic receptors can help to alleviate symptoms of parkinsons disease.
dental complications of parkinsons disease
-motor control impairments. reduced jaw muscle function, difficulty in brushing and flossing, oral tremor or dyskinesia, difficulty in swallowing.
xerostomia or sialorrhea, nausea and vomiting.
orthostatic hypotension, and walking problem
levodopa may sensitize the heart to epinephrine induced tachycardia.
COMT inhibitor interaction with epinephrine.
