Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
25 Cards in this Set
- Front
- Back
|
How does levodopa work?
|
It is an precursor to dopamine, metabolized to dopamine by dopa decarboxylase.
|
|
|
What is the main disadvantage of levodopa?
|
95% of it is metabolized in the periphery; only 2% reaches the brain.
|
|
|
What drug is given with levodopa to minimize peripheral consumption?
|
Carbidopa
|
|
|
How does carbidopa work?
|
It inhibits dopa decarboxylase, but it can't cross the BBB so it doesn't affect levodopa in the brain.
|
|
|
What are some side effects of levodopa?
|
dyskinesias, N/V, postural hypotension, psychotic behavior
|
|
|
What are the drug interactions with levodopa?
|
with pyridoxine, increased peripheral metabolism of levodopa; with reserpine, depleted dopamine stores; with antipsychotics, blocked dopamine receptors; with MAOI, hypertensive crises; with anticholinergics, reduced GI absorption
|
|
|
What is the mechanism of action of bromocriptine?
|
It is a dopamine receptor 2 agonist.
|
|
|
What other disease does bromocriptine treat?
|
hyperprolactinemia
|
|
|
What are the side effects of bromocriptine?
|
involuntary movement, N/V, arrhythmias, postural hypotension
|
|
|
When is bromocriptine contraindicated?
|
in patients with recent MI or psychiatric illness
|
|
|
What may happen on the first dose of bromocriptine?
|
sudden cardiovascular collapse
|
|
|
Name three other dopamine agonists and which receptors they agonize.
|
Pergolide (D1 and D2), ropinerole (D2), pramipexole (D3)
|
|
|
What is the mechanism of action of amantadine with respect to treatment of parkinson's disease?
|
It stimulates the release of dopamine from presynaptic vesicles and delays reuptake.
|
|
|
What other disease does amantadine treat?
|
influenza A
|
|
|
What are the side effects of amantadine?
|
livedo reticularis, peripheral edema
|
|
|
What is the mechanism of action of selegiline (L-deprenyl)?
|
It is an inhibitor of MAO-B.
|
|
|
What is MAO-B?
|
monoamine oxidase B, only metabolizes dopamine
|
|
|
Why would you give anticholinergic drugs to a patient with parkinsonism?
|
Dopamine usually inhibits cholinergic neurons in the striatum, so when it's gone, there's too much cholinergic activity.
|
|
|
Name some anticholinergic drugs.
|
benztropine, biperiden, orphenadrine, procyclidine, trihexyphenidyl
|
|
|
What are the side effects of anticholinergic drugs?
|
sedation, confusion, dry mouth, constipation, urinary retention, blurred vision, tachyarrhythmias
|
|
|
What are the drug interactions with anticholinergics?
|
tricyclic antidepressants, antihistamines
|
|
|
What do you give for tremor?
|
beta-blockers - propranolol
|
|
|
What do you give for Huntington's disease?
|
neuroleptics - haloperidol and the phenothiazines (both block dopaminergic receptors)
|
|
|
What do you give for Tourette syndrome?
|
neuroleptics - haloperidol (D2 receptor blockers)
|
|
|
What causes Huntington's disease?
|
degeneration of striatal GABA-ergic and cholinergic neurons; deficiency of cholinergic function
|
