Parkinson's disease is a disorder of the brain that leads to
shaking (tremors) and difficulty with walking, movement, and
coordination. Paralysis agitans; Shaking palsy Causes,
incidence, and risk factors Parkinson's disease most often
develops after age 50. It is one of the most common nervous
system disorders of the elderly. Sometimes Parkinson's disease
occurs in younger adults. It affects both men and women. In some
cases, Parkinson's disease occurs in families. When a young
person is affected, it is usually because of a form of the
disease that runs in families. Nerve cells use a brain chemical
called dopamine to help control muscle movement. Parkinson's
disease occurs when the nerve cells in the brain that make
dopamine are slowly destroyed. Without dopamine, the nerve cells
in that part of the brain cannot properly send messages. This
leads to the loss of muscle function. The damage gets worse with
time. Exactly why these brain cells waste away is unknown.
Parkinson's in children may occur because the