Wk 10 Parkinson Dx Flashcards
ft’s of Parkinson
tremor, rigidity, bradykinesia, postural instability
death occurs from complications
Parkinson Patho
loss of dopaminergic neurons in substantia nigra
Parkinson motor complications
50-90% of pt’s on levodopa >/= 5 yrs develop this
“wearing off” and “on-off” effect
wearing off effect
initially, tx by dosing more often (shorten dosing interval)
later on, add a dopamine agonist
on-off effect
tx with rescue apomorphine or adjust dose/freq of levodopa
Pharmocotherapy of Parkinson
replacement of Dopamine, inhibition of dop breakdown, stimulation of dop rec, administration of anticholinergics
physical disability is progressive and unavoidable
therapy initiation/dosing is highly individualized
Levodopa
mainstay of tx since 60’s, most effective agent
crosses BBB (dopamine DOES NOT)
sig peripheral adverse effects
always administered with peripheral DDC inhibitor (carbidopa)
competes for abs with other AA
GI upset minimized by giving with low protein meals
Carbidopa
most respond to 750-1000 mg of LD
after 8 tabs/day of 25/100 mg, switch
allows greater individualization for patients with advanced Parkinson
COMT inhibitors
peripheral and central effects
MAOB inhibitors
selective MAO-B inhibitor prolongs dop effects
modest effects
usually used as adjective in advanced cases
minimize tyramine intake
avoid concomitant use of SSR (serotonin syndrome)
Selegiline
may improve wearing off effect by 50-70%
less effective improving on-off effects
Dopmine Agonist- ergot derivative (1st generation)
Bromocriptine: rarely used now
inc risk of pericardial fibrosis and cardiac valve fibrosis
pramapexole + LD
did better than LD alone
less dyskinesias, wearing off effects and motor complications
Anticholinergics in Parkinson
mainstay of tx until late 60’s
SE: constipation, dry mouth, blurred vision, confusion and urinary retention
Amantadine
primarily an antiviral found to have anti-Parkinson activity
previously used as early monotherapy
now used as add-on for levodopa induced dyskinesias
