Movement disorders pharm Flashcards
dopamine agonists (DA)
bromocriptine pramipexole ropinirole rotigotine apomorphine
monoamine oxidase inhibitors
rasagiline
selegiline
COMT inhibitors
entacapone
tolcapone
antimuscarinic agents
benztropine biperiden orphenadrine procyclidine trihexyphenidyl
levodopa MOA
agonist at D2R
levodopa PK
take 30-60min before meals
only 1-3% reaches brain
combo w/carbidopa reduces peripheral meta of levodopa
levodopa GI
w/o 80% experience anorexia, nausea, and vomiting
levodopa CV
postural hypotension
tachycardia, ventricular extrasystoles, rarely afib
d/t increased peripheral catecholamines
HTN can occur w/large doses
levodopa behavioral
depression anxiety agitation insomnia somnolence confusion delusions hallucinations nightmares euphoria more common w/combo
levodopa dyskinesia
80% of pt taking drug >10yrs
wearing off phenomenon
each dose of L-dopa effective for 1-2hrs with rapid return of rigidity and akinesia
on-off phenomenon
marked akinesia alternating with improved movement with no coordination to timing of drugs
DDIs levodopa
Pyridoxine- increases extracerebral metabolism may prevent therapeutic effect unless peripheral decarboxylase inhibitor
MAOIs-HTN, do not give if taking MAOIs or w/in 2 wks of discontinuation
DA MOA
act directly on postsynaptic DRs
do not require enzymatic conversion
no potentially toxic metabolites
do not compete w/another substance for transport across BBB
uses of DAs
certain pts respond better to certain drugs
1st line therapy for parkinsons
use is associated w/less fluctuations and dyskinesias then L-dopa
generally those who do not respond to L-dopa do not respond to DAs
can be added to L-dopa
bromocriptine
ergot alkaloid derivative
D2 agonists
extensive first pass
can also be used for endocrine disorders
pramipexole
D3Rs
renal insufficiency- must be dose adjusted
RLS
ropinirole
D2Rs
RLS
rotigotine
DA
may have serious site application rxns
DA GI
anorexia, nausea, vomiting (should be taken w/meals)
DA CV
postural hypotension ergot derivatives (bromocriptine)- painless digital vasospasm