Parkinson’s disease—also called paralysis agitans—is a movement disorder resulting from the loss of dopamine-producing cells in the brain. The disorder is chronic and progressive, which means that the symptoms develop gradually and worsen over time.

At least 500,000 people in the United States currently have Parkinson’s disease. The risk of Parkinson’s disease increases with age and is greater in men than in women. The average age of Parkinson’s onset is 60 years old, though about 5-10 percent of cases are described as early-onset, meaning they occur in people under age 50.

Parkinson’s Disease Symptoms

The four main symptoms of Parkinson’s disease are listed below; however, each of these symptoms can occur in other disorders, as well.

  • Trembling of the hands, arms, legs, jaw or head
  • Stiffness of the limbs and trunk
  • Slowness of movement
  • Impaired balance

As the symptoms worsen, people with Parkinson’s disease may have difficulty walking, talking or performing simple physical tasks. They may also develop secondary symptoms, such as:

  • Difficulty chewing and swallowing
  • Depression
  • Lack of facial expression
  • Speech changes
  • Urinary problems
  • Constipation
  • Muscle cramps and pain
  • Dementia
  • Sleep problems
  • Oily skin
  • Excessive sweating
  • Fatigue and loss of energy
  • Low blood pressure when getting up from a lying position
  • Sexual dysfunction