Treatment of Parkinson's Disease ll Flashcards
Anticholinergics
- limited use in PD
- primarily used to control tremors
- CNS acting
Anticholinergics example
- Trihexyphenidyl
- Benztropine
- longer acting
Anticholinergic side effects (4)
- Dry mouth
- Constipation
- Blurred vision
- Sedation
Glutamate activity on NMDA receptors
- associated with neurotoxicity (glutamate)
- activates NMDA receptors which activates processes that encourage cell death
- increase glutamatergic activity linked to
~ development of and maintenance of levodopa-induced dyskinesias
Hence, NMDA antagonists inhibit glutamate activity
NMDA antagonists examples (2)
- Amantadine
- Memantine
- no good evidence on use for levodopa-induced dyskinesias (not recommended for clinical use)
- can use for mild-moderate alzheimer’s disease
Amantadine MOA
- Upregulates D2 receptors and increase D2 receptors sensitivity
- NMDA antagonists
- Anticholinergic
Unknown primary MOA
NMDA antagonists features (3)
- renal excretion
- can be stimulating (2nd dose in afternoon, not at night)
- avoid concurrent use with memantine (overstimulation)
NMDA antagonists place in therapy (2)
- Adjunctive to levodopa
- Manage levodopa-induced dyskinesia
- if prescribed tgt with levodopa, can tell patient on levodopa for at least 3-5 years resulting in dyskinesia
ADR of NMDA antagonists (6)
- N/V
- Light-headedness
- Insomnia cos stimulating
- Confusion
- Hallucinations
- Livedo reticularis
Alternative/complementary medicines for PD (8)
- Co-enzyme Q10
- Creatine
- Vit E
- Glutathione
- Riboflavin
- Lipoic acid
- Acetyl carnitine
- Curcumin
However, studies have :
- inconclusive results
or
- they show safety but lack efficacy
Parkinsonism types
- Vascular parkinsonism
2. Drug-induced parkinsonism
Vascular parkinsonism
- many subtypes but all display signs and symptoms of PD
- due to vasculature in brain
Vascular parkinsonism symptoms (6)
- Bilateral
- No resting tremors
- Stepwise in progression
- increase insult to brain, deterioration progress - Vascular risk factors present
- Increasing age is a risk factor
- VPD patients are older than those with PD - Not caused by infarct/lesions in basal ganglia
- other parts of the brain
Treatment for PD = Treatment for VPD?
No. Treatment for PD is ineffective for VPD
iPD vs DIP (6)
DIP
- symmetrical
- acute or subacute onset
- may or may not be reversible
- poor response to levodopa
- common in females
- uncommon for freezing
iPD
- asymmetrical
- chronic onset
- not reversible, progressive
- marked response to levodopa
- common in males
- common for freezing
DIP
Drug-induced parkinsonism
- may unmask existing PD (bring forward PD symptoms earlier)
- course is variable (3months onset)
- not always reversible
- prevention is the best treatment
DIP treatment (3)
- withdrawal of the offending drug usually leads to improvements in symptoms in 80% of patients in 8 weeks
- anticholinergics
- amantadine
DIP offending drugs (4)
- Antipsychotics
- higher dose for atypicals antipsychotics - Dopamine antagonists
- Antidepressants
- SSRI - Levothyroxine
PHS
Parkinson Hyperpyrexia Syndrome (PHS)
PHS causes
- Changes in dopaminergic treatment
- Provoked by trauma, surgery, & pulmonary, GI and urinary tract infections
- No apparent trigger
PHS management (5)
If cause is due to reduction in dopaminergic medications,
- reinstate previous treatment
- increase dose of levodopa gradually
- Rotigotine patch or amantadine injections if cannot PO
- dantrolene
- bromocriptine (ergot derivative dopamine agonist)
Severe PHS
- no response to dopaminergic rescue medications
- symptoms deteriorate rapidly
- progressively more rigid and immobile
Systemic complications of PHS (4)
- Reduce consciousness leading to aspiration pneumonia
- Rhabdomyolysis leading to acute renal failure
- Immobility leading to DVT and PE
- DIVC (disseminated intravascular coagulation)
PD patients in acute care require what inputs?
- require inputs from a range of HCP because the impact of PD is very wide
Professionals involved in care of PD patients (8)
- Doctors
- Nurses
- Pharmacists
- Physiotherapists
- strengthening exercise so patients do not lose their muscle function and gait - Occupational therapists
- maintain independence in ADL
- remain safe at work - Nutritionists
- maintain balance diet to reduce muscle loss - Speech therapists
- project voice to communicate
- proper swallowing - Medical social worker
- social support
Why are PD patients admitted to hospitals
- Admitted with parkinsonian features but without known PD (not diagnosed until admission)
- Known PD but admitted for unrelated problem
- Known PD and admitted for specific complications of PD
- Admitted with parkinsonian features but without known PD (not diagnosed until admission)
- differential diagnosis : DIP, essential tremors
- accurate diagnosis is impt but difficult due to concurrent illness
- specialist advice recommended
- Known PD but admitted for unrelated problem
- most patients not admitted to neurological or geriatric unit
- need to review meds (avoid anti-dopaminergics & anticholinergics)
- screen for possible related problems
- arrange for specialist input
- Known PD and admitted for specific complications of PD
Complications of PD
- aspiration pneumonia
- dopamine agonist withdrawal
- psychosis
- dyskinesia
Medication review (6)
- Correct preparation?
- sustained release or immediate release
- Madopar vs Madopar HBS vs Madopar dispersible - Correct ratio?
- sinemet 1:4 and 1:10 - Can patient swallow the pills whole?
- Sinemet SR/CR cannot crush
- Madopar HBS must be swallowed whole - DDI
- dopamine antagonist
- anti-emetics (prochlorperazine)
- SSRI - Comorbidities
- depression (SSRI)
- BPH use alpha blockers (worsens hypotension) - Individual specific time of administration
ISMP’s recommendations (14)
- Expedite reconciliation of orders
- Allow recreation of administration schedules
- Avoid non-formulary delays
- Know the symptoms
- Avoid contraindicated drugs
- Build alerts
- Neurology consultation
- Manage NBS
- Do not abruptly discontinue meds (PHS)
- Promote swallowing
- Optimal surgery time
- Focused education (of staff)
- Patient education
- Report ADR