Parkinson's disease is a progressive neurological condition affecting movements such as walking, talking and writing. Parkinson's has three main symptoms: tremor, stiffness and slowness of movement (bradykinesia).

The cause of Parkinson's is not completely understood. A group of nerves in the brain called the substantia nigra slowly degenerate and cease to produce a chemical messenger called dopamine. When more than half of dopamine is lost, the symptoms of Parkinson's disease are produced.

Parkinson’s disease cannot be cured. Treatment focuses on managing symptoms and generally involves medications which attempt to replace the dopamine that is lacking.

There is a no single test to diagnose Parkinson’s disease.  In its early stages a diagnosis of Parkinson’s disease can be very difficult even for an experienced doctor. Even then a period of observation and reassessment may be needed before the diagnosis is confirmed.

The diagnosis is based on:
• the person’s medical history and symptoms
• the  neurological and physical examination
• imaging techniques such as computerised tomography (CT) or magnetic resonance imaging (MRI) may be used to rule out other conditions.