The most common form of the disease is called idiopathic parkinsonism
and has no known cause. It has no known hereditary component, nor is it
contagious. Parkinsonism affects women and men in equal proportions.

There is also drug-induced parkinsonism, which is caused mostly
by drugs to treat severe mental illness. This form of parkinsonism is
usually reversed when the drug is discontinued or its dosage decreased.
Parkinsonism also may be caused by disorders such as encephalitis and
hardening of the arteries (arteriosclerosis), or following certain
brain injuries, including those caused by a stroke.

Mechanism of Parkinsonism

Parkinsonism is believed to be related to the substantia nigra
(black substance) of the nerve cells, which produce and store a
chemical substance called dopamine–one of several neurotransmitters.
(A neurotransmitter relays messages from the brain across a small open
space–or synapse–at the junction of the nerves.) Parkinson’s disease
apparently interferes with dopamine storage and/or production, which
causes disturbances in nerve message transmission. This, in turn, leads
to shaking or other defective motor responses. In addition to dopamine
depletion, parkinsonism also seems to involve an excess of cholinergic
activity. Treatment, therefore, entails either increasing the
concentration of dopamine or decreasing the concentration of
acetylcholine, another neurotransmitter that causes symptoms of
Parkinson’s disease when dopamine levels are reduced. Both treatments
are often used.

Symptoms of Parkinson’s Disease

Parkinson’s disease usually starts very gradually. Early symptoms,
which may go unnoticed for years, include stiffness of the hands,
fatigue or weakness, depression and a slight limp or changes in
posture. The symptoms increase and eventually may develop into
full-blown parkinsonism, exhibiting muscular rigidity, tremor and
slowness of movement. Other symptoms vary from patient to patient and
may include soft, monotonous or slow speech, difficulty in swallowing,
trouble in walking, shuffling, a change in bowel habits, slow
urination, excessive sweating or drooling. Symptoms often are limited
to one side of the body. Diagnosis is sometimes assisted by analysis of
the patient’s handwriting, which may show evidence of tremor, is
typically small and tends to decrease in size with the passage of time.

Treatment of Parkinson’s Disease

A short while ago, a diagnosis of parkinsonism was a lifelong
condemnation. But parkinsonism has become a very treatable condition,
and many patients are able to function normally for many years.

Since the cause of the disease is still unknown, therapy is
aimed at relieving symptoms. Treatment usually consists of drug
therapy, physical therapy and the use of devices (such as a typewriter,
instead of writing by hand, or a speech amplifier) that permit patients
to lead productive lives. Treatment does involve trial and error, and
both doctor and patient must persevere in an attempt to find the best
individual combination of drugs and dosages. Drug treatment usually
entails supplying the brain with the missing neurotransmitter,
dopamine. These drugs are called dopamine precursors. Some patients
react best when the excessive acetylcholine is inhibited through the
use of anti-cholinergic drugs.

Exercises

Exercises are usually prescribed by the doctor, who may refer the patient to a physical therapist.

General physical condition is also important, and patients are
encouraged to develop general exercise routines for home practice.

General Tips

Summing Up

Parkinsonism is a serious but treatable disease. As with most chronic
illness, patients may be depressed, anxious and fearful. Parkinson’s
disease patients and their families may contact a voluntary health
agency for support and information.