Parkinson's disease (PD) is a long-term degenerative disorder of the central nervous systemthat mainly affects the motor system. The symptoms generally come on slowly over time. Early in the disease, the most obvious are shaking, rigidity, slowness of movement, and difficulty with walking. Thinking and behavioral problems may also occur. Dementiabecomes common in the advanced stages of the disease. Depression and anxiety are also common occurring in more than a third of people with PD. Other symptoms include sensory, sleep, and emotional problems. The main motor symptoms are collectively called "parkinsonism", or a "parkinsonian syndrome."
Parkinson's disease Symptoms

The Stages of Parkinson's Disease
Parkinson's disease strikes people in many different ways, leaving them to experience a broad range of symptoms. Though symptoms may be mild or severe or occur frequently or infrequently, Parkinson's disease appears to have five different stages. The time spent at each stage varies, and the skipping of stages, from stage one to stage three, for example, is not uncommon.
Parkinson's disease stages include:
Stage one: During this initial phase of the disease, a person usually experiences mild symptoms, such as tremors or shaking in a limb. During this stage, friends and family can usually detect changes caused by Parkinson's, such as poor posture, loss of balance, and abnormal facial expressions.
Stage two: In the second stage of Parkinson's disease, the person's symptoms are bilateral, affecting both limbs and both sides of the body. The person usually encounters problems walking or maintaining balance, and the inability to complete normal physical tasks becomes more apparent.