Parkinson's disease can affect you in four main ways: shaking, having stiff muscles, having slow movements and having poor balance. The symptoms are usually mild at first and you may not need any treatment for a while.
Symptoms tend to progress slowly and in no particular order.  Parkinson's disease affects everyone differently, and you probably won't get all of these symptoms.
Shaking (doctors call this tremor or resting tremor)
One of your hands may shake, especially when you're relaxing. But the shaking stops when you're asleep or moving.
The shaking is worse when your hand is resting or you're stressed.
Shaking usually affects one side of your body, especially early on in the disease.
Many people rub their thumb and index finger together as if rolling a pill.
As the shaking gets worse, you may not be able to hold a cup or newspaper steady.
Shaking can also affect your neck, chin and head.
Shaking is an important symptom for many people. But about a quarter of people never get it.
Stiff muscles (doctors call this rigidity)
Some of your muscles may be tense because they're not getting the right messages from your brain.
This makes you stiff, and you may find it difficult to move. For example, you may find it difficult to get out of a chair.
Your face may seem less expressive because the muscles there aren't moving as well as they normally would.
Your muscles may resist or jerk if someone tries to move part of your body (your arm, for example). Doctors call this cogwheel rigidity.
Slow movements (doctors call this bradykinesia or akinesia)
You may find it hard to start moving because instructions from your brain take longer to get to your nerves and muscles.
You may stay in the same position for longer than usual without moving.
You may have problems moving smoothly. This can be frustrating and unpredictable. You can be moving easily one minute and then suddenly need help.
Tasks you once did quickly and easily, such as washing and dressing, may take much longer.
Your handwriting may look spidery and small.
Poor balance (doctors call this postural instability)
You may lean forwards or backwards and fall over easily.
You may have problems walking.
You may freeze in midstride and not be able to take the next step. Doctors call this freezing of gait or FOG for short.
You may take quick, small, shuffling steps. Doctors call this festination.
You may stop naturally swinging your arms as you walk.
Your symptoms might not be obvious during the early stage of the disease. Your friends or relatives may be the first to notice changes. For example, they may see that your face doesn't light up when you laugh.
As the disease progresses, your symptoms may start to get in the way of what you want to do. For example, you might find it hard to hold a cup steadily.
You may also get other problems, such as depression and trouble swallowing and chewing. See Other problems linked with Parkinson's disease to learn more. Some of these problems may appear early in the disease and some later.
It's important to keep track of your symptoms so that you can tell your doctor how they have changed since your last visit. In fact, you might want to keep a diary of your symptoms to show your doctor.
This information will help a specialist decide when you should start taking medication and when you need to change your treatment. You may see your doctor for many years before they think you should take treatment for Parkinson's disease.
National Institute of Neurological Disorders and Stroke. Parkinson's disease: hope through research. Available at http://www.ninds.nih.gov/disorders/parkinsons_disease (accessed on 18 September 2007).
Parkinson's Disease Society. About Parkinson's. What is Parkinson's? Available at http://www.parkinsons.org.uk (accessed on 18 September 2007).
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