According to the University of Maryland Medical Center, Parkinson's disease is a disease of the nervous system that worsens over time. In people with Parkinson's disease, the neurons, or nerve cells, in a section of the brain known as the substantia nigra degenerate. While the disease cannot be cured, treatment can help symptoms dramatically. Since there are no blood tests that can prove that a person has Parkinson's disease, it is particularly important to recognize the early symptoms of the disorder.
Causes
Symptoms in Parkinson's disease do not become noticeable until 80 percent of the cells of the substantia nigra have died. Once this happens, a neurotransmitter called dopamine is lost and the messages normally relayed by dopamine to the motor centers cannot get through. This results in the motor dysfunction that is typical in Parkinson's disease. Unfortunately, it is unknown what causes the cells in the substantia nigra to die.
Types
As discussed on MayoClinic.com, the four main symptoms of Parkinson's disease are tremor, rigidity, akinesia and postural instability. Tremor is a trembling of the arms or legs that is not controlled by the patient. A resting tremor or a sensation of trembling, noted by the patient, is often the first symptom. Rigidity refers to stiffness that can limit range of movements. This is often first noted when a patient stops swinging his arms while walking. Akinesia is a slowness of starting movements. Finally, postural instability refers to difficulty with maintaining balance.
Other Symptoms
Other early symptoms of Parkinson's disease are changes in speech, facial expressions and behavior. Often a patient will speak more softly and will take longer to initiate a sentence. Family members sometimes note that a patient seems less animated when talking or seems to stare more often and blink less. While problems with memory and problem solving usually occur later in the disease course, mild symptoms may occur before diagnosis.
Identification
There is not a blood test that can diagnose Parkinson's disease, so diagnosis is based on symptoms and on physical examination. Identifying Parkinson's disease on the basis of symptoms alone can be complicated because other problems, such as toxins and certain medications, can cause these symptoms. Symptoms are more likely to be caused by Parkinson's disease if they start on only one side of the body, if the tremor is more obvious at rest and if there is improvement with medication that is used to treat Parkinson's disease.
Treatment
Treatment for Parkinson's disease can help to alleviate symptoms. The first medication used is called levodopa-carbidopa. This medication helps to increase dopamine in the brain and thus reduce the motor symptoms of Parkinson's disease. Other drugs mimic dopamine in the brain and can reduce symptoms in that manner. Examples of these drugs include bromocriptine, pramipexole and ropinirole.
