A chronic, slowly progressive disease of the nervous system, also known as paralysis agitans or shaking palsy. Its manifestations are the result of the degeneration of nerve ganglia at the base of the brain. There is no known cause of Parkinson's disease although it may follow encephalitis or atheroma. Parkinson's disease is rare before age 50 and affects more men than women. Early symptoms include fine tremors in the hands, arms and legs and involuntary nodding of the head. Later the facial muscles begin to tighten and the expression becomes fixed and mask-like. Gradually, as muscular tremors affect the whole body, limbs become stiff and walking increasingly difficult until it is reduced to a stooped shuffle of small, rapid steps.
There is no known cure for Parkinson's disease but some of the more distressing symptoms like stiffness and tremors may be relieved by specific drug treatment. Exercise and massage are also helpful. In most cases, people suffering from this disease become depressed as their mobility and independence are curbed. Support agencies have been established to help both those people suffering from Parkinson's disease and their family members.