Symptoms of Parkinson’s disease tend to emerge slowly and are often subtle at first. However, in some patients, they may progress quickly. Symptoms usually affect just one side of the body initially before moving to the other side. Even when the symptoms begin to affect both sides of the body, the patient usually experiences more severe symptoms on one side than the other.  

There are four major symptoms commonly associated with Parkinson’s disease. They are:

• Tremor. A trembling in the hands, arms, legs, jaw and face. The tremors are most obvious when a person is at rest. In Parkinson’s disease, the tremor often appears as a characteristic back-and-forth motion that occurs at the rate of between four and six beats per second. It also often involves rubbing of the thumb and forefinger that is described as a “pill rolling” motion.
  
  
• Rigidity. A stiffness of the limbs and trunk that results from muscles being constantly tensed and contracted. It is most obvious when another person tries to move the patient’s arm, which typically responds in short and jerky movements. This is known as cogwheel rigidity.
  
  
• Bradykinesia. Slowness of movement. People with Parkinson’s disease may take several hours to perform simple tasks such as washing or dressing.
  
  
• Postural instability. Impaired balance and coordination. Patients often fall easily and may develop a stooped posture.

Patients who display these symptoms are said to have parkinsonism. This term encompasses both Parkinson’s disease and other disorders that mimic Parkinson’s disease but that are caused by other factors (e.g., taking certain medications or having Lewy body dementia). When symptoms first appear, it is usually unclear whether patients have Parkinson’s disease or one of these other conditions.

Some people with Parkinson’s disease display all the symptoms of the disease, although certain symptoms may be more pronounced. Tremors are the most characteristic symptom of Parkinson’s disease. However, some people with Parkinson’s disease experience very mild or nonexistent tremors.

Because Parkinson’s disease usually develops gradually, patients may be unaware of their symptoms at first. They may notice that they have a slight tremor in one hand or that their handwriting seems smaller and more cramped than usual. Friends and family members may also notice that the patient moves unusually slowly or has a blank facial expression.

As symptoms progress, patients with Parkinson’s disease may find that their tremor interferes with daily activities. They may also have difficulty chewing, swallowing and speaking. Urinary problems, constipation and skin conditions (e.g., oily or dry skin, excessive sweating) are also associated with this disease.

Other motor symptoms associated with Parkinson’s disease include:

• Difficulty initiating any voluntary movement
  
• Difficulty arising after sitting
  
• Difficulty turning in bed
  
• Shuffling walk
  
• Small steps followed by a brief run to maintain balance while walking
  
• Reduced swinging of the arms
  
• Lack of facial expression or animation in the face
  
• Small handwriting (micrographia)

Other nonmotor-related symptoms associated with Parkinson’s disease include:

• Drooling
  
• Erectile dysfunction in men
  
• Foot cramps
  
• Increased perspiration
  
• Lower voice volume
  
• Reduced sense of smell

Some patients with Parkinson’s disease develop dementia as the disease progresses. This condition, called Parkinson’s dementia, may cause memory loss, difficulties with language and lack of social judgment. 

Patients who are diagnosed with Parkinson’s disease often experience great anxiety about the progressive nature of the disease and may excessively monitor their symptoms. Others may begin to avoid social situations for fear of being embarrassed by their condition. Some patients may experience sleep disturbances, depression (which may be exacerbated by the loss of dopamine that occurs with Parkinson’s disease) and other emotional changes as the disease progresses.