Fortunately, symptoms of the disease do respond well to medical treatments. One of these treatments, levodopa, has been considered the cornerstone of Parkinson’s disease therapy for nearly 40 years. It is normally very effective when it is first used to treat the disease. Over a number of years, however, some people may see changes in the way their medication controls their symptoms. These changes are commonly known as motor fluctuations.

Over time, you may find that your symptoms begin to come back before it is time to take your next dose of levodopa medication. This change in symptoms is called “wearing-off.”

As “wearing-off” becomes more noticeable, you may find that the amount of time that you have a good response to levodopa (known as “on” time) shortens. The time that you have a poor response to levodopa (known as “off” time) may lengthen.

It is important to recognize when your symptoms return during the day. It could mean you are experiencing “wearing-off.” It may be possible to better control these symptoms by changing or adjusting your treatment.

As these motor fluctuations emerge, other unwanted side effects may occur. These include involuntary movements you cannot control, known as dyskinesia (e.g. twisting/turning movements) or dystonia (e.g. prolonged muscle cramping).

Why do motor fluctuations occur?
In the early stages of the disease, the brain is able to store enough dopamine. This permits smoother release of dopamine in the brain. It also provides a more constant control of symptoms. However, as Parkinson’s disease gets worse, the brain has fewer cells that can take up levodopa and store it as dopamine for release when levels are low. Because of this reduced ability to store dopamine in the brain, symptoms may return after shorter periods of time (e.g. “wearing-off”). If someone with a reduced ability to store dopamine is given too much levodopa, it may lead to side effects (e.g. dyskinesia).