parkinsons Flashcards
Parkinson’s disease
- A degenerative brain disorder affecting movement
- Leads to gradual loss of muscle control
- Not fatal but progressive and incurable
- Severely affects quality of life
- Involves the loss of dopinegic neurons in the substantial nigra part of the brain
- Leads to abnormally low dopamine levels
Risk factors for PD
• Older age
o Due to accelerations of normal age related deterioration of neurons
• Oxidative damage
o Free radicals may potentially damage molecules generated through normal chemical reactions in the body
• Environmental factors
o An external or internal toxin which destroys the neurons
• Genetic predisposition
• Medications
Parkinsonism types
• An umbrella term
• Vascular parkinsonism
o Multiple small strokes in key areas of the brain may cause parkinsonism
• Dementia with lewy bodies
o Progressive problems with memory and flu cations in thinking as well as hallucinations
o Slowness stiffness
• Drug induced parkinsonism
o Most common form of secondary parkinsonism
o Side effects of certain medications especially those affecting brain dopamine leves
Symptoms of PD
- Tremor
- Rigidity
- Akinesia: difficulty in intiating movement and slowness of movement
- Postural instability
TREATMENT of PD
• Non pharmological strategies o Conselling and education o Providing information o Engage in physical activity o Physiotherapy o Supportive care • Pharmological treatments o Provide symptomatic relief o Meducations are used to increase levels of dopamine or to inihibt the actions of acetylcholine in the brain o No agents slow progression of disease • Functional neurosurgery o Deep brain stimulation
levodopa
a prodrug that is converted to dopamine by DOPA decarboxylase and can cross the blood-brain barrier
side effects • Nausea and vomiting • Postural hypotension • Cardiac arrhythimas • Constipation • Sudden sleep episodes • Impulse control disorders • Confusion
Dopamine agonists
• Effective first line drugs
• Improve bradykinesia and rigidity less effective than levodopa
• No significant difference in outcomes between pateitns started on levodopa/dopa decarboxylase inihibtos and those given dopamine agonist
o Common as time progression
• Cabergoline bromocriptine and pergolide
• Monitoring is essential chest x ray respiratory function
• Efficacy and safety of oral dopamine agonists similar
• Pramipexole rotiotine ropiniroe
o Good symptomatic therapy
o Less dyskinesias motor flucations compared to levodopa
o Available as once daily dosing in oral and topical forms
• Side effects
o Impulse control
o Hypersexuality
o Neuropsychiatric. Effects
• Cabergoline bromocriptine and pergolide
o Side effects similar to levodopa
Monoamine oxidase type b inhibitors
• Rasagiline and selegiline
o Reduce breakdown of dopamine and may also block dopamine reuptake
o Marketed for use as monotherapy and as un adjunct to levodopa in later stage disease
o Less effective than levodopa and dopamine agonists
o Side effects hypotension dyskinesia heachache
Anticholinergic agents
- Barely used
- Benzhexol benztropine and biperiden
- Bad side effects
Medications to avoid
- Anti nausea medications eg metoclopramide
* Antipsychotic medications eg haloperidol
Different types
- Idiopathic (unknown) Parkinsonism: most common
- Vascular Parkinsonism: from multiple small strokes in key areas of the brain
- Dementia with Lewy Bodies: progressive problems with memory + fluctuations in thinking, hallucinations PLUS other typical Parkinson’s symptoms (slowness, stiffness)
- Drug-induced Parkinsonism: caused by certain medications, especially those affecting brain dopamine levels e.g. antipsychotics/antidepressants, antiemetics
Non-pharmacological strategies
- Counselling and education for pts and carers
- Providing information about medications to avoid
- Physical activity, maintain core balance in strength to improve gait and postural stability
- Physiotherapy to improve motor function
- Supportive care in advanced phases of PD when drugs become poorly tolerated
Treatment choice
- Patient’s age
- Symptoms and severity – is QOL impacted?
- Duration of PD
- If patient can tolerate side effects
- How well the medicines work overall
