Chapter 30 Agents Used to Treat Parkinson’s Disease.
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Transcript of Chapter 30 Agents Used to Treat Parkinson’s Disease.
Chapter 30
Agents Used to Treat Parkinson’s Disease
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Parkinson’s Disease
A neurological disorder characterized by: Muscle tremors Muscle rigidity Lack of coordination Drooling Shuffling gait Postural changes
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Parkinson’s Disease
Slow onset – several months to years Approximately 1 million Americans affected Usually develops between the ages of 45-69 Women and men equally affected Family history not a factor Progressive disease, if not treated causes
death Cause is not completely understood
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Parkinson’s Disease
Imbalance of dopamine and acetylcholine levels in the brain
Levels of other neurological chemical decrease:Gamma-aminobutyric acid (GABA)SerotoninNorepinephrine
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Classes of Anti-Parkinson Agents
Dopaminergic agentsCatechol-O-methyltransferase
inhibitorsCholinesterase inhibitorsAnticholinergic agents
Classes of Anti-Parkinson Agents
Non-ergot dopamine agonists (direct-acting dopamine receptor agonists) May be classified as “dopaminergic”
Indirect-acting dopamine receptor agonists (monoamine oxidase inhibitors, or MAOIs) Also can be classified as “dopaminergic”
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Dopaminergic agents
Levodopa prototype Most effective drug treatment Acts peripherally Rapidly converts to dopamine Symptoms subside or disappear
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Levodopa
Therapeutic effects Therapeutic intensity varies Dosage dependent
Adverse effects Nausea and vomiting Orthostatic hypotension Cardiac arrhythmias
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Carbidopa/Levodopa (Sinemet)
Carbidopa prevents levodopa from being broken down in the peripheral circulation
Improves neurological-skeletal muscle activity
Combining these agents reduces the required Levodopa dose by 25% Carbidopa, 10 mg / Levodopa,100
mg dose
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Amantadine (Symmetrel)
Anticholinergic/dopaminergic in action
Treats viral disorders such as influenza
Acts as an anti-Parkinson agent; it exerts an additive effect on LevodopaIncreases CNS dopamine
concentration
Other dopaminergic anti-PD drugs
Parlodel (bromocriptine mesylate) Ergot derivative; may allow reduced
maintenance levodopa dosage Mirapex (pramipexole dihydrochloride)
Nonergot; treats tremors, shaking, slow movements
Also treats restless leg syndrome Can cause hypotension – teach slow position
transition
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Other dopaminergic anti-PD drugs
Requip and RequipXL (ropinirole) Also treats RLS Lowers B/P
Neupro (rotigotine) patch Nonergot; treats early-stage PD Sleep attacks
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Other dopaminergic anti-PD drugs
Zelapar (selegiline HCl) Indirect-acting dopamine receptor agonist
/monoamine oxidase inhibitor
Patch developed for antidepressant (Emsam)
MAOIs – high risk of interaction with other medications Check for contraindications
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Newest class of anti-Parkinson drug agents
Treats clients with history of poor response to levodopaSustains dopaminergic levels
Brain remains stimulated
Catechol-O-Methyltransferase Inhibitors
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Catechol-O-Methyltransferase Inhibitors
Adverse effects Liver failure Dyskinesia Orthostatic hypotension Dystonia Somnolence GI irritation
Note interactions with other drugs
Catechol-O-Methyltransferase Inhibitors
Adjuncts to levodopa Comtan (entacapone)
Many interactions with other drugs Tasmar (tolcapone)
Liver damage
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Cholinesterase inhibitors
Exelon (rivastigmine) – origin as Alzheimer’s drug (see Ch. 28)
Apokyn (apomorphine HCl) SQ “rescue” drug for undermedicated, “frozen”
state. Four- to eight-minute onset give with antiemetic r/t morphine; not analgesic, no dependency
risk
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Anticholinergic Agents
Reduces excessive cholinergic brain activityExample: trihexyphenidyl (Artane)
Used for clients with minimal symptoms
Adjunct with other agents Caution: narrow-angle glaucoma
Anticholinergic Agents
Inhibit acetylcholine in PNS Cogentin (benztropine mesylate) Akineton (biperiden HCl) Kemadrin (procyclidine)
Adjunct agentsUse with minimal symptomsS
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Adverse Effects of Anticholinergics
Dry mouthUrinary retentionConstipation
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Nursing Considerations
Patients on levadopa (not Sinemet) should not take vitamin B6
Educate patient on disease process, medication therapy goals, and adverse effects and what to do about them
Assure adequate fluidsCounsel patients to be careful when
doing activities that require alertness
Nursing Considerations
Assess for need for other supportive therapies such as physical, occupational, and speech
High protein food may decrease absorption of levadopa
Assess patients self care abilities on an ongoing basis
Assess fall risk on an ongoing basis
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