Alzheimer's and Parkinson's Flashcards
Dopamine and acetylcholine role in smooth movements
dopamine inhibits, acetylcholine excites
neurotransmitters involved in parkinson’s
dopamine and acetylcholine
Most effective drug for Parkinson’s
Levodopa/carbidopa=sinemet
Levodopa mechanism of action
lifts dopamine levels by converting to dopamine in the brain
carbidopa MOA
drives levodopa across the BBB by decreasing breakdown of levodopa in the periphery by DDC.
how long does levodopa have an effect
about 5 years – often won’t use it in 60 year olds
What enzyme breaks down levodopa, allowing only 2% of blood to reach the brain
DDC. When carbidopa blocks that enzyme, 10% of it goes across the BBB
SE of levodopa/carbidopa
MOST COMMON: n/v (don’t take with high-protein meals), dyskenesia
Other systems: CV postural hypotension, dysrhythmias; NEURO psychosis 20%, anxiety, agitation, memory but don’t use 1st gen antipsychotic; GU darkened sweat and urine; activate malignant melanoma
Most common SE of levodopa/carbidopa
n/v, dyskinesia
Cardiovascular SE of Levodopa/Carbidopa
postural hypotension, dysrhythmias – sometimes need salt pills
CNS effects of levodopa/carbidopa
psychosis (but don’t use a 1st gen antipsychotic), anxiety, agitation, memory issues
Integumentary/excretion SE of levodopa/carbidopa
- darkened sweat and urine
- maybe activate malignant melanoma
Acute loss of effect for levodopa/carbidopa
- wears off at end of the dosing interval
- minutes to hours where it stops working (avoid high protein meals)
Dopamine agonist prototype
pramipexole (Mirapex)
1st line therapy for mild to moderate symptoms and for younger patients who are more likely to handle side effects
dopamine agonists: pramipexole
younger patients – the babies get pushed in the pram
weird side effect of pramipexole
pathological gambling and other compulsive self-rewarding behavior
SE of monotherapy pramipexole
daytime sleepiness (sleep attack), insomnia, hallucinations, nausea, dizziness, constipation, weakness
SE of levadopa + pramipexole
orthostatic hypotension, dyskinesia, double rate of hypotension
what else is pramipexole used for
restless leg syndrome
COMT inhibitor prototype
entacapone (comtan)
Levodopa booster
COMT inhibitor – no direct therapeutic effects on their own
SE of COMT inhibitors (entacapone)
increased levo SE, GI distress, yellow/orange discoloration of urine
MAO-B inhibitors prototype
selegiline (Eldepryl)
Why are MAO-B inhibitors used in parkinson’s
Reduce levodopa wearing-off effect, suppress destruction of dopamine and prolong the effects of levodopa
SE of selegiline (MAO-B inhibitors)
insomnia, orthostatic hypotension, dizziness, GI symptoms
Unexpected drug for parkinson’s
amantadine (antiviral)
Why does an antiviral help with Parkinson’s
can help with dyskinesias caused by levodopa
SE of amantadine for Parkinson’s
CNS, anticholinergic, benign livedo reticularis (mottled skin discoloration)
anticholinergic prototype
benztropine (cogentin)
who gets an anticholinergic for parkinson’s
younger patients – it’s on the BEERS list
function of cholinesterase
breaks down acetylcholine
MOA of cholinesterase inhibitors
Inhibits cholinesterase, making ACh available to neurons
are cholinesterase inhibitors effective?
Ummm, statistically but not clinically. They also don’t bring back anything that’s already been lost.
SE of cholinesterase inhibitors
pro-cholinergic: rest and digest, bronchoconstriction, n/d, bradycardia, fainting, falls
Administration considerations for cholinesterase inhibitors
give at night, slowly titrate up
NMDA receptor antagonists prototype
memantine (namenda)
MOA for NMDA receptor antagonists (memantine)
allows calcium influx into neuron
SE of memantine
related to toooooo much calcium entering: dizziness, headache, confusion, constipation (but very well tolerated)
