Parkinson’s Disease

What is Parkinson’s Disease?

Parkinson’s disease (PD) is a neuro-degenerative disorder that affects predominantly dopamine-producing (“dopaminergic”) neurons in a specific area of the brain called substantia nigra. Dopamine is an organic chemical and is required for transmitting neuro signals in the human body. Dopamine depletion can directly affect motor functions, hence greatly inhibits a patient’s ability to move. This disease is often found in people of 60 years old or above, but some patients can be as young as 30 years of age.


There is no known reason for the loss of nerve cells associated with Parkinson’s disease. Ongoing research is needed to identify potential causes, including genetic changes and environmental factors.


Movement symptoms

In general, the main symptoms include tremors, rigidity, bradykinesia and prone to losing balance when walking.

  • Early-stage:
    Tremors: Uncontrolled tremors of arms and legs occur continuously or intermittently, especially at rest. The tremors start with a hand or a foot and then slowly spread to the rest of that side of the body.
    Rigidity: The muscles of hands and feet become stiff. A client may notice significant increase of resistance when straightening or bending a limb.
    Bradykinesia (slow movement): This may present as difficulty in writing, with handwriting getting progressively smaller and squiggly, no postural change during a long period of sitting, difficulty in taking a step forward and then stopping or lacking facial expression etc.
  • The intermediate stage:
    It is characterised by symptoms spreading from one side to both sides of the body (bilateral involvement) or at the midline without impairment to balance. Other symptoms include:
    On-off fluctuations of drug effects.
    Unsteady posture when standing or walking, e.g. feet not lifted but dragged on the ground while walking.
    losing balance and falling easily. body leaning forward with small shuffling steps or finding it difficult to initiate a step and turn.
  • Late-stage:
    Symptoms become severe and debilitating. Functional activities and mobility are significantly affected in drug-off periods. Clients need assistance and assistive equipment to perform normal daily tasks, and they may experience advanced symptoms such as speech and swallowing problems, incontinence, Dyskinesia (involuntary movements), loss of self-care abilities, cognitive dysfunction and mental impairments such as hallucination and delusion.

Non-movement symptoms

  • Cognitive changes: problems with attention, planning, language, memory or even dementia
  • Constipation
  • Feeling full after eating small amounts
  • Excessive sweating, often when medication wears off
  • Fatigue
  • Increase in dandruff (seborrheic dermatitis)
  • Hallucination and delusion
  • Lightheadedness (orthostatic hypotension): drop in blood pressure when standing
  • Loss of sense of smell or taste
  • Mood disorders, such as depression, anxiety, apathy and irritability
  • Pain
  • Sexual problems, such as erectile dysfunction
  • Sleep disorders, such as insomnia, excessive daytime sleepiness (EDS), REM sleep behavior disorder (RBD), Restless Legs Syndrome (RLS)
  • Urinary urgency and frequency, and incontinence
  • Vision problems, especially when attempting to read items up close
  • Weight loss



With regular dosages of medication, the symptoms can be controlled through:

  • Increasing the amount of dopamine
  • Slowing down the metabolism of dopamine in the brain
  • Blocking the action of acetylcholine in the brain
  • Drugs replenishing/mimicking dopamine may alleviate symptoms but there may be side effects


Deep Brain Stimulation

  • Implant a probe, electrode or stimulator into a specific brain region with blocking or inhibiting counter-current, to regulate abnormal neural signal transmission and to relieve the symptoms of Parkinson’s disease. This new technology has already been introduced in Hong Kong.


  • Apply stretching exercises and movement strategies to improve mobility and correct abnormal movement patterns and postures
  • Aerobic exercises and muscle strengthening programs to improve joint flexibility
  • Balance and endurance training to improve mobility abilities

Occupational therapy

  • Home assessments and modifications to prevent falls at home
  • Postural assessment and seating modification to reduce the risks of lower back pressure and structural deformity caused by joint rigidity
  • Training on the use of assistive aids and equipment, e.g. large-handled cutlery with easier grips
  • Functional activities and fine motor tasks training to facilitate independent self-care
  • Cognitive training
Occupational therapy
Occupational therapy

Speech therapy

Improve a client’s speech and swallowing problem

Speech therapy
Speech therapy

Other Targeted Service Users

Mild Cognitive Impairment (MCI)


Chronic Pain

Spinal Cord Injury


Traumatic Brain Injury

Developmental disorders and physical disabilities

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