Movement Disorders Meds Flashcards
Parkinsons Tx Class: Levodpa/Carbidopa -medication name -medication effectiveness -SE of prolonged use? -MOA -Adverse Effects -CI -Precautions
Name:Levodopa/carbidopa (Sinememt) “GOLD STANDARD”
Effectiveness decreases after 3 years of tx and may return to pretreatment levels in 6-7yrs; relieves akinesia, rigidity, and tremor
SE: prolonged use may directly hasten the degeneration of dopamine neurons in the substantia nigra
MOA: levadopa is an immediate metabolic precursor to dopamine, penetrates the brain where its converted to dopamine. Carbidopa is given in conjunction to inhibit the conversion to dopamine before it reaches the BBB
Adverse Effects:
- Physical:
- -low BP, arrhythmia, GI effects, hair loss, dyskinesias**
- psychiatric:
- -confusion, anxiety, vivid dreams, hallucinations
CI: concurrent use with MAOI’s, psychotic pts, angle-closure glaucoma, hx of melanoma (melanoma is dopamine driven)
Precautions:
- cardiac dz
- PUD
Parkinsons Tx: Class; MOA-B inhibitors -medication names -MOA -adverse effects -Caution -CI
- Slegiline may have neuroprotective properties
- Rasagiline
MOA: stops the breakdown of dopamine
Adverse Effects: Insomnia(take in AM), jitteriness, dyskinesias, orthostatic hypotension
Caution:
- Psychiatric Disorders*
- CV dz
- seizures
- hyperthyroid
- DM
CI:
-TCAs, SSRIs, Demerol
Parkinsons Tx Class: Dopamine Agonists -medication names -MOA -Adverse Effects -CI
Newer:
- Ropinirole (requip)
- Pramipexole (mirapex)
Older agents:
- pergolide (permax)
- bromocriptine(dont use much d/t fungus attacking heart valves)
MOA: wakes up receptor sites to increase dopamine utilization
*only use when sinemet effectiveness is declining as add on therapy, when we add this on we decrease sinemet.
Adverse effects:
- drowsiness/sleepiness
- Nausea and constipation
- HA
- ortho Hypotension
- nasal congestion
- nightmares, hallucinations, psychosis
- dyskinesias
CI:
- pts with psychotic illness
- recent MI
- PUD
Parkinsons Tx Class: COMT inhibitors -medications -moa -adverse effects
Entacapone (Comtan), Tolcapone (Tasmar)
MOA: inhibits dopamine breakdown by selectively inhibiting COMT.
Adverse effects:
- involuntary muscle movements
- mental confusion/hallucination s
- cramps, Nausea, diarrhea
- insomnia, HA
- urine discoloration
try this for 2-3 weeks and if its not working then stop it and you dont do it again
Parkinsons Tx: Class: Amantidine -MOA -when is this useful? -SE
MOA: potentiates the dopaminergic function by influenciig the synthesis, release, or reuptake of dopamine.
-useful for early mild sx
SE:
-sedation, vivid dreams, dry mouth, depression, hallucinations
Parkinsons Tx:
- Class: Ach Blocking
- medications
- MOA
- Adverse effects
- CI
Trihexyphenidyl (Artane), Benztropine (Cogentin)
MOA: blocks Ach thereby blocking inhibition, so Ach not as effective in blocking dopamine.
Adverse Effects
-CNS: drowsiness, mental slowness, restlessness, confusion, hallucination
-SYstemic: dry mouth, blurred vision, consitpation, urinary retention
CI:
-BPH, obstructive GI dz, angle closure glaucoma
Parkinsons Tx:
-Class: NMDA receptor inihibtors
Apomorphine (Apokyn) ??
Patient with mild parkinsons, what medication is used first line?
selegiline, this is the only medication that may provide benefit with slowing some progression of the dz
If experienceing the “wearing off effect” while taking sinemet what is the next best step?
how can you prevent this “wearing off effect”?
bridge therapy; add on COMT inhibitor*, MAOBs, dopamine agonists
Prevention:
- multiple small doses on empty stomach to maintain a constant level
- liquid form
- controlled release formulation
What are some causes of the wearing off effect?
- dz progresses beyond the ability of levodopa to control it
- become tolerant to prolonged exposure to dopamine
- dopamine neurons become incapable of storing dopamine and when the levodopa wears off there is no dopamine remaining.
- L-dopa itself accelerates the dz by producing oxygen free radicals, this increases injuries to the brain and dopamine degredation
Dopamine Agonists:
- AMpomorphine (apokyn)
- -use
- -SE
Use: treat acute episodes of “hypermobility or freezing” give subQ
SE: profound nausea, must be given with antiemetic (NOT zofran, kytril b/c they block dopamine)
Symptomatic treatment of mild parkinsons is probably best avoided until there is some degree or disability or sx begin to have a significant impact on ADLs, T/F?
True
Despite the fact that the benefits of levadopa diminish with time, evidence is accumulating that dopaminergic therapy at a relatively early stage may be the most effective in alleviating sx and may affect the mortality rate d/t the dz, t/f?
True
