Topic Overview
What is Parkinson's disease?
Parkinson's disease
affects the way you move. It happens when there is a problem with certain nerve
cells in the brain.
Normally, these nerve cells make an important
chemical called
dopamine. Dopamine sends signals to the part of your
brain that controls movement. It lets your muscles move smoothly and do what
you want them to do. When you have Parkinson's, these nerve cells break down.
Then you no longer have enough dopamine, and you have trouble moving the way
you want to.
Parkinson's is progressive, which means it gets
worse over time. But usually this happens slowly, over many years.
And there are good treatments that can help you live a full life.
What causes Parkinson's disease?
No one knows for
sure what makes these nerve cells break down. But scientists are doing a lot of
research to look for the answer. They are studying many possible causes,
including aging and poisons in the environment.
Abnormal
genes
seem to lead to Parkinson's disease in some
people. But so far, there is not enough proof to show that it is always
inherited.
What are the symptoms?
The four main symptoms of
Parkinson's are:
- Tremor, which
means shaking or trembling. Tremor may affect your hands, arms, or legs.
- Stiff muscles.
- Slow movement.
- Problems with balance or walking.
Tremor may be the first symptom you notice. It's one of
the most common signs of the disease, although not everyone has it.
More
importantly, not everyone with a tremor has Parkinson's disease.
Tremor often
starts in just one arm or leg or on only one side of the body. It may be worse
when you are awake but not moving the affected arm or leg. It may get better
when you move the limb or you are asleep.
In time, Parkinson's
affects muscles all through your body, so it can lead to problems like trouble
swallowing or constipation.
In the later stages of the disease, a person with
Parkinson's may have a fixed or blank expression, trouble speaking, and other
problems. Some people also lose mental skills (
dementia
).
People usually start to have
symptoms between the ages of 50 and 60. But sometimes symptoms start
earlier.
How is Parkinson's disease diagnosed?
Your doctor
will ask questions about your symptoms and your past health and will do a
neurological exam. This exam includes questions and tests that show
how well your nerves are working. For example, your doctor will watch how you
move, check your muscle strength and reflexes, and check your vision.
Your doctor will also ask
questions about your mood.
In some
cases, your doctor may have you try a medicine. How this medicine works may
help your doctor know if you have Parkinson's disease.
There are no lab or blood tests that
can help your doctor know whether you have Parkinson's. But you may have tests
to help your doctor rule out other diseases that could be causing your
symptoms. For example, you might have an
MRI
to look for signs of a
stroke
or
brain tumor
.
How is it treated?
At this time, there is no cure
for Parkinson's disease. But there are several types of medicines that can
control the symptoms and make the disease easier to live with.
You may not even need treatment if your symptoms are mild. Your doctor
may wait to prescribe medicines until your symptoms start to get in the way of
your daily life. Your doctor will adjust your medicines as your symptoms get
worse. You may need to take several medicines to get the best results.
Levodopa (also called L-dopa) is the best drug for controlling symptoms
of Parkinson's. But it can cause problems if you use it for a long time
or at a high dose. So doctors sometimes use other medicines to treat people in the early stages of the disease.
The decision to start
taking medicine, and which medicine to take, will be different for each person. Your doctor will be able to help you make these
choices.
In some cases, a treatment called deep brain stimulation
may also be used. For this treatment, a surgeon places wires in your brain. The
wires carry tiny electrical signals to the parts of the brain that control
movement. These little signals can help those parts of the brain work
better.
There are many things you can do at home that can help you
stay as independent and healthy as possible. Eat healthy foods. Get the rest
you need. Make wise use of your energy. Get some exercise every day. Physical
therapy and occupational therapy can also help.
How will Parkinson's disease affect your life?
Finding out that you have a long-term, progressive disease can lead to a wide range of feelings. You may feel angry,
afraid, sad, or worried about what lies ahead. It may help to keep a few things
in mind:
- Usually this disease progresses slowly. Some people live for
many years with only minor symptoms.
- Many people are able to keep working
for years. As the disease gets worse, you may need to change how you work.
- It is important to take
an active role in your health care. Find a
doctor you trust and can work with.
- Depression is common in
people who have Parkinson's. If you feel very sad or hopeless, talk to your
doctor or see a counselor.
- It
can make a big difference to know that you're not alone. Ask your doctor about
Parkinson's support groups, or look for online groups or message
boards.
- Parkinson's affects more than just the person who has it.
It also affects your loved ones. Be sure to include them in your decisions.
Frequently Asked Questions
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Learning about Parkinson's disease:
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Being diagnosed:
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Getting treatment:
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Ongoing concerns:
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Living with Parkinson's disease:
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Cause
Low levels of
dopamine
, a brain chemical involved
in controlling movement, cause symptoms of Parkinson's disease. Low levels happen when nerve cells in a part of the brain that makes dopamine break down. The exact cause of this
breakdown isn't known.
Scientists are looking for links between
Parkinson's disease and genetics,
aging, toxins in the environment, and
free radicals
. Although
these studies are beginning to provide some answers, experts don't know the
exact cause of the disease.
Only a small
percentage of people with Parkinson's have a parent, brother, or sister
who has the disease. But abnormal
genes
do seem to be a factor in a few families where
early-onset Parkinson's is common.
There are many other causes
of parkinsonism, which is a group of symptoms that includes tremor, muscle
stiffness, slow movement, and unsteady walking. Parkinsonism mimics Parkinson's
disease, but in fact is not Parkinson's disease.
Symptoms
Symptoms of Parkinson's disease differ from person to person. They also change as the disease progresses. Symptoms that one person gets in
the early stages of the disease, another person may not get until later—or
not at all.
Symptoms typically begin
appearing between the ages of 50 and 60. They develop slowly and often go
unnoticed by family, friends, and even the person who has them.
The disease causes motor symptoms and non-motor symptoms. Motor symptoms are those that have to do with how you move. The most common one is tremor.
Tremor
Tremor, or shaking, often in a hand,
arm, or leg, occurs when you're
awake and sitting or standing still (resting tremor), and it gets better when you move that body part.
Tremor is often the first symptom that people with
Parkinson's disease or their family members notice.
At first the tremor may
appear in just one arm or leg or only on one side of the body. The tremor also
may affect the chin, lips, and tongue.
As the disease progresses, the tremor
may spread to both sides of the body. But in some cases the tremor remains
on just one side.
Emotional and physical stress tends to make the
tremor more noticeable. Sleep, complete relaxation, and intentional movement or
action usually reduce or stop the tremor.
Although tremor is one
of the most common signs of Parkinson's, not everyone with tremor has
Parkinson's. Unlike tremor caused by Parkinson's, tremor caused
by other conditions gets better when your arm or hand is not moving and gets
worse when you try to move it.
The most common cause of non-Parkinson's tremor
is essential tremor. It's a treatable condition that is often
wrongly diagnosed as Parkinson's.
Other common symptoms
Besides tremor, the most common symptoms
include:
-
Stiff muscles (rigidity) and aching muscles. One of the most
common early signs of Parkinson's is a reduced arm swing on one side
when you walk. This is caused by rigid muscles. Rigidity can also
affect the muscles of the legs, face, neck, or other parts of the body. It may
cause muscles to feel tired and achy.
-
Slow, limited movement,
especially when you try to move from a resting
position. For instance, it may be hard to get out of a chair or turn over
in bed.
-
Weakness of face and throat muscles. It may get harder to talk and swallow. You may choke, cough, or
drool. Speech becomes softer and monotonous. Loss of movement in the muscles in
the face can cause a fixed, vacant facial expression, often called the
"Parkinson's mask."
-
Difficulty with walking and
balance. A person with this disease is likely to
take small steps and shuffle with his or her feet close together, bend forward
slightly at the waist, and have trouble turning around.
Balance and posture problems may cause frequent falls. But these
problems usually don't happen until later on.
-
Freezing
, a sudden, brief inability to move. It most
often affects walking.
A
small number of people have symptoms on only one side of the body that never
move to the other side.
Non-motor symptoms
Parkinson's disease can cause many other symptoms that aren't related to how you move. These can be disabling and may include things like constipation, sleep problems, and depression.
There are many
other conditions with symptoms similar to Parkinson's disease. Some of these
may be reversible.
What Happens
Treatment may help control
symptoms during the early
stages of Parkinson's disease. It is usually started
as soon as symptoms begin to affect your ability to work or do daily
activities. As the
disease progresses, drugs may become less effective.
Early stage
Tremor
is
usually the first symptom, appearing in just one arm
or leg or on only one side of the body. With time, the tremor usually—but not always—spreads
to both sides of the body. Joint pain, weakness, and fatigue may occur.
Moderate stage
As the disease gets worse, the person may have slow
movement, stiff muscles, and poor coordination. He or she may have problems with tasks such as writing,
shaving, or brushing teeth. Changes in handwriting are common.
Problems
with posture and balance develop. A person with Parkinson's tends to
walk in a stooped manner with quick, shuffling steps.
Advanced stage
After
several years, as muscle stiffness and tremor increase, the person may become
unable to care for himself or herself. He or she may
be confined to a wheelchair or bed.
People who have taken medicine for several years
may not only notice their symptoms getting worse but also may start to have other movement problems. These
motor fluctuations can be reduced somewhat by making changes in the person's
medicine, but they can be difficult to control and may further complicate
treatment.
Dementia
may develop in up to one-third
of people who have late-stage Parkinson's disease.
1
Dementia symptoms may include disorientation at night, confusion, and memory
loss. Medicines that are used to treat Parkinson's disease can also
contribute to this problem.
What Increases Your Risk
A risk factor is anything that increases your chances of getting sick or having a problem. Risk factors for
Parkinson's disease are hard to identify, because
the cause of the disease is unknown.
Getting older
Advancing age is the only known risk
factor for typical Parkinson's disease (not including early-onset Parkinson's).
Most instances of Parkinson's occur after age 50. But the illness
does occur in people between the ages of 30 and 50 or, in rare cases, at a
younger age.
Family history
A very small number of people with Parkinson's have a
close relative who also has the disease. But it doesn't appear that a family
history of typical Parkinson's significantly increases your risk for the disease.
Having a family history of the disease is a more
significant risk factor in cases of early-onset Parkinson's, but this
form of the disease is not common.
Poisons in the environment
Some research suggests that
long-term exposure to certain environmental risk factors such as pesticides,
chemicals, or well water may increase a person's risk of developing Parkinson's
disease. But this has not been proved.
When To Call a Doctor
Call 911 or other emergency services immediately if signs of a
stroke
develop suddenly. These may include:
- Sudden numbness, tingling, weakness, or loss of movement in your face, arm, or leg, especially on only one side of your body.
- Sudden vision changes.
- Sudden trouble speaking.
- Sudden confusion or trouble understanding simple statements.
- Sudden problems with walking or balance.
- A sudden, severe headache that is different from past headaches.
If you develop a tremor
Urgent medical
care isn't needed if you have had a tremor—shaking or trembling—for some time. But you should
discuss the tremor at your next doctor's appointment.
If a tremor is affecting
your daily activities or if it is a new symptom, see your doctor sooner.
A written
description will help your doctor make a correct diagnosis. In writing your
description, consider the following questions:
- Did the tremor start suddenly or
gradually?
- What makes it worse or better?
- What parts of
your body are affected?
- Have there been any recent changes in the
medicines you are taking or how much you are taking?
If you have Parkinson's disease
If you have been diagnosed with Parkinson's, call your doctor if:
- You notice any significant change in your
symptoms, such as severe episodes of freezing—a sudden loss of mobility—which
may affect walking.
- Your response to your medicine
changes.
- Any other
symptoms occur, such as constipation, sexual problems, or incontinence.
- You have
symptoms of depression, such as feeling sad and hopeless and losing interest in daily activities.
- You or your family
notice that you have problems with memory and thinking ability.
Who to see
The following health professionals can help diagnose or
treat Parkinson's disease:
Other health professionals who may be involved in your
care include:
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Exams and Tests
A diagnosis of
Parkinson's disease is based on your
medical history and a thorough
neurological exam.
Your doctor also may check your
sense of smell.
In some cases, your doctor will have you try a medicine for
Parkinson's disease. If that medicine helps your symptoms, it may help the
doctor find out if you have the disease.
Tests
There are no lab
tests that can diagnose Parkinson's.
But if your doctor isn't sure you have Parkinson's, he or she may do certain tests to see if you have another condition with similar symptoms.
For instance,
blood tests may be done to check for abnormal thyroid hormone levels or liver
damage. An imaging test (such as a
CT scan or an
MRI) may be used to check for signs of a
stroke
or brain tumor.
Another type of
imaging test, called
PET, sometimes may detect low levels of dopamine in
the brain, a key feature of Parkinson's. But PET scanning isn't
commonly used to evaluate Parkinson's because it's very expensive, not available in many hospitals, and only used experimentally.
Treatment Overview
No known treatment can stop or reverse the breakdown of nerve cells that causes Parkinson's disease. But there are many treatments that can help your symptoms and improve your quality of life.
Your age, work status, family, and living situation
can all affect decisions about when to begin treatment, what types of treatment
to use, and when to make changes in treatment. As your medical condition
changes, you may need regular changes in your treatment to balance
quality-of-life issues, side effects of treatment, and treatment costs.
You'll need to see members of your health care team regularly (every 3 to 6
months, or as directed) for adjustments in your treatment as your condition
changes.
Treatments for Parkinson's include:
-
Medicines, such as levodopa and dopamine agonists. This is the most common treatment for Parkinson's disease. For more information, see Medications.
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Home treatment. There are many steps you
can take at home to make dealing with the symptoms of Parkinson's disease
easier, such as getting regular exercise and eating a healthy diet. For more information, see Home Treatment.
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Surgery. Brain surgery can help a small number of people with the disease. For more information, see Surgery.
-
Speech therapy
. Speech therapists use breathing and speech exercises to help you overcome the soft,
imprecise speech and monotone voice that develop in advanced Parkinson's
disease.
-
Physical therapy
. Therapists may help you improve your walking and reduce your risk of falling.
-
Occupational therapy
. Therapists can help you learn new ways to do things for yourself so you can stay independent longer.
-
Treatment for mental problems. You or your family members may notice that
you begin to have problems with memory, problem solving, learning, and other
mental functions. When these problems keep you from doing daily activities, it
is called
dementia
. There are medicines that can help treat
dementia in people with Parkinson's.
Depression
Depression is common in people with
Parkinson's disease.
Recognizing and dealing with depression is important. There are medicines that can help the
symptoms of depression in people with Parkinson's.
Your doctor, other health
professionals, or Parkinson's support groups can help you get emotional
support and education about the illness. This is important both early and
throughout the course of the disease.
Prevention
There is no known way to prevent
Parkinson's disease.
Research has shown
that people who eat more fruits and vegetables, high-fiber foods, fish, and
omega-3 rich oils (sometimes known as the Mediterranean diet) and who eat less
red meat and dairy may have some protection against Parkinson's. But
the reason for this is still being studied.
2
Home Treatment
Early on,
Parkinson's disease may not greatly disrupt your life. But for most people, the
disease becomes more disabling over time. Home treatment can help you adjust as
time goes on and help you stay independent for as long as possible.
Your home and lifestyle
-
Modify your activities and your home. For example, simplify your daily activities and change the
location of furniture so that you can hold on to something as you move around
the house.
-
Eat healthy foods, including plenty
of fruits, vegetables, grains, cereals, legumes, poultry, fish, lean meats, and
low-fat dairy products.
-
Exercise and do physical therapy. They have benefits in both early and advanced stages of the
disease.
Motor problems
Mood and mental problems
-
Deal with depression. If you are
feeling sad or depressed, ask a friend or family member for help. If these
feelings don't go away, or if they get worse, talk to your doctor. He or she
may be able to suggest someone for you to talk to. Or your doctor may give you medicine that
will help.
- Deal with
dementia
. Dementia is common late in Parkinson's
disease. Symptoms may include confusion and memory loss. If you (or a family
member) notice that you are confused a lot or have trouble thinking clearly,
talk to your doctor. There are medicines that can help dementia in people with
Parkinson's disease.
Medications
Medicines are the most common treatment
for
Parkinson's disease. The goal is to correct the
shortage of the brain chemical
dopamine
, which causes the symptoms of Parkinson's.
The decision to start
taking medicine, and which medicine to take, will be different for each person. Medicine is usually started when your symptoms become disabling
or disrupt your daily activities.
Symptoms change as the
disease progresses. Because of this, your doctor will adjust your drugs to deal
with the symptoms as they appear.
Drugs often improve symptoms, but they also may cause side effects. It
may take some time to find the best combination of drugs for you.
Medication choices
Several drugs may be used at
different stages of the disease:
Levodopa is thought to be the most effective drug for controlling symptoms. But many doctors prescribe dopamine agonists in the beginning of the disease. This is because after a few years, levodopa can cause motor complications (times when the medicine suddenly stops working or when
you have uncontrollable jerking movements). Talk to your doctor about which drugs are best for you.
Although it's always important to follow your doctor's
instructions when you take medicines, it's especially vital when you have Parkinson's.
Increasing, decreasing, or stopping
the medicines you are taking may cause big changes in your symptoms and can be
dangerous. Even if a medicine doesn't seem to be working, when you stop taking
it, your symptoms of Parkinson's disease may be worse.
Taking medicine with food
Early in the disease, it might be helpful to take pills with food to help
with nausea, which may be caused by some of the medicines for Parkinson's
disease.
Later in the disease, taking the medicines at least 1 hour before
meals (and at least 2 hours after meals) may help them work best.
Some
medicines for Parkinson's disease don't work as well if you take them at the
same time you eat food with protein in it, such as meat or cheese. The protein
can block the medicine and keep it from working as well as it should.
Surgery
Brain surgery may be considered when drugs
fail to control symptoms of
Parkinson's disease or cause severe or disabling side
effects.
Surgery isn't a cure. Drugs are usually still
needed after surgery. But you probably won't need as much medicine as before, which means you may have fewer side effects.
People who have
very advanced Parkinson's or who have other serious problems (such as
heart or lung disease, cancer, or kidney failure) usually aren't good
candidates for surgery. Surgery usually isn't considered for people who have
dementia
or psychiatric disorders.
Surgery choices
-
Deep brain stimulation uses electrical impulses to stimulate a target area in the brain. It's
the preferred surgery for treating most cases of advanced Parkinson's.
-
Pallidotomy involves
the precise destruction of a very small area in a deep part of the brain that
causes symptoms.
-
Thalamotomy involves
the precise destruction of very small area in another part of the brain that
causes symptoms.
Neurotransplantation is an experimental procedure being studied for the treatment of
Parkinson's disease. It involves implanting cells that produce dopamine into
the brain. Information about how well neurotransplantation works is
limited. And it is not a proven treatment or a realistic option for most people
at this time.
See a neurologist
A neurologist with special
training in Parkinson's disease is most often the best kind of doctor to make a
decision about surgery. If you might benefit from surgery or deep brain
stimulation, your neurologist can refer you to a brain surgeon with experience
doing these operations.
Other Treatment
Physical therapy,
speech and language therapy, and
occupational therapy can all be helpful for people
who have
Parkinson's disease.
Special diets
Several nutritional
therapies have been suggested as treatments for Parkinson's. None of
these have been proved effective. But it is important to maintain general
health and to eat a
balanced diet.
Before trying a
complementary treatment, such as a special diet, talk with your doctor about
the safety and potential side effects of the treatment. Talking
with your doctor can help you both decide whether a treatment is safe and
effective. Complementary treatments should not replace the use of drugs to
treat Parkinson's if you are a candidate for treatment with these
drugs.
Electroconvulsive therapy
Depression that does not respond to drugs may improve with
electroconvulsive therapy
(ECT). ECT can also improve
movement for a short period of time, though the reason for this improvement isn't understood.
Other Places To Get Help
Organizations
|
National Institute of Neurological Disorders and
Stroke
|
| NIH Neurological Institute |
| P.O. Box 5801 |
| Bethesda, MD 20824 |
| Phone: | 1-800-352-9424 |
| Phone: | (301) 496-5751 |
| TDD: | (301) 468-5981 |
| Web Address: | www.ninds.nih.gov |
| |
|
The National Institute of Neurological Disorders and
Stroke (NINDS), a part of the National Institutes of Health, is the leading
U.S. federal government agency supporting research on brain and nervous system
disorders. It provides the public with educational materials and information
about these disorders.
|
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|
American Parkinson Disease Association
(APDA)
|
| 135 Parkinson Avenue |
| Staten Island, NY 10305 |
| Phone: | 1-800-223-2732 |
| Phone: | (718) 981-8001 |
| Fax: | (718) 981-4399 |
| Email: | apda@apdaparkinson.org |
| Web Address: | www.apdaparkinson.org |
| |
|
This not-for-profit organization has information and
referral centers in most states to provide information on local health
services, availability of doctors experienced with the disease, and updated
information on medications. APDA has 90 fundraising chapters and more than 400
support groups nationwide.
|
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National Parkinson Foundation (NPF)
|
| 1501 NW 9th Avenue / Bob Hope Road |
| Miami, FL 33136-1494 |
| Phone: | 1-800-4PD-INFO (1-800-473-4636) |
| Phone: | 1-800-327-4545 |
| Phone: | (305) 243-6666 |
| Fax: | (305) 243-6073 |
| Email: | contact@parkinson.org |
| Web Address: | www.parkinson.org |
| |
|
The National Parkinson Foundation provides information
on problems related to Parkinson's disease. It also maintains the Bob Hope
National Parkinson Research and Rehabilitation Institute. NPF conducts research
on Parkinson's disease, provides doctor referrals, and sponsors a variety of
educational programs.
|
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Parkinson's Disease Foundation
|
| 1359 Broadway |
| Suite 1509 |
| New York, NY 10018 |
| Phone: | 1-800-457-6676 |
| Phone: | (212) 923-4700 |
| Fax: | (212) 923-4778 |
| Email: | info@pdf.org |
| Web Address: | www.pdf.org |
| |
|
This national not-for-profit organization is dedicated
to research on the cause, prevention, treatment, and cure of Parkinson's
disease and related conditions. It maintains laboratories and grants
postdoctoral and student fellowships. It also provides referrals to support
groups and neurologists.
|
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WE MOVE
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| 5731 Mosholu Avenue |
| Bronx, NY 10471 |
| Email: | wemove@wemove.org |
| Web Address: | www.wemove.org |
| |
|
WE MOVE is an Internet resource for movement disorder
information. This nonprofit organization is dedicated to educating people about the latest
treatment options for neurologic movement disorders. WE MOVE also has
information on support groups and hosts discussions and chat rooms on the website.
|
|
References
Citations
-
Buter TC, et al. (2008). Dementia and survival in
Parkinson disease: A 12-year population study. Neurology, 70(13): 1017–1022.
-
Sofi F, et al. (2008). Adherence to Mediterranean diet
and health status: Meta-analysis. BMJ. Published online
September 11, 2008 (doi:10.1136/bmj.a1344).
Other Works Consulted
- Deuschl G, et al. (2006). A randomized trial of
deep-brain stimulation for Parkinson's disease. New England Journal of Medicine, 355(9): 896–908.
- Miyasaki JM, et al. (2002). Practice parameter: Initiation of treatment for Parkinson's disease (an evidence-based review). Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology
, 58(1): 11–17. Also available online: http://www.neurology.org/content/58/1/11.full.html.
- Olanow CW, et al. (2009). A double-blind, delayed-start trial of rasagiline in Parkinson's disease. New England Journal of Medicine, 361(13): 1268–1278.
- Stowe R, et al. (2010). Evaluation of the efficacy and safety of adjuvant treatment to levodopa therapy in Parkinson's disease patients with motor complications. Cochrane Database of Systematic Reviews (7).
- Suchowersky O, et al. (2006). Practice parameter:
Diagnosis and prognosis of new onset Parkinson disease (an evidence-based
review). Report of the Quality Standards Subcommittee of the American Academy
of Neurology. Neurology
, 66(7): 968–975. Also available online: http://www.neurology.org/content/66/7/968.full.
- Suchowersky O, et al. (2006). Practice parameter:
Neuroprotective strategies and alternative therapies for Parkinson disease (an
evidence-based review). Report of the Quality Standards Subcommittee of the
American Academy of Neurology. Neurology
, 66(7):
976–982. Also available online: http://www.neurology.org/content/66/7/976.full.
- Weintraub D, et al. (2010). Impulse control disorders in Parkinson disease. Archives of Neurology, 67(5): 589–595.
- Zesiewicz TA, et al. (2010). Practice parameter: Treatment of nonmotor symptoms of Parkinson's disease: Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology
, 74(11): 924–931. Also available online: http://www.neurology.org/content/74/11/924.full.
Credits
|
By
| Healthwise Staff |
|
Primary Medical Reviewer
| Anne C. Poinier, MD - Internal Medicine |
|
Specialist Medical Reviewer
| G. Frederick Wooten, MD - Neurology |
|
Last Revised
| August 2, 2012 |
