by EBSCO Medical Review Board
(PD; Paralysis Agitans; Shaking Palsy)


Parkinson disease (PD) is a brain disorder that causes tremors and problems moving.

Part of the Brain Affected by PD—Yellow Section
Substansia Nigra
Copyright © Nucleus Medical Media, Inc.


Dopamine is a chemical in the brain. It helps people move and control their emotions. PD is caused by a loss of brain cells that make dopamine. It is not known why this happens.

A small number of people with PD have an early-onset form. This type is caused by a faulty gene. It is passed down from parents.

Risk Factors

PD is more common in older adults. Other things that may raise the risk are:

  • Family members with PD
  • Exposure to toxins, such as well water and pesticides


Symptoms start slowly and get worse over time. Common ones may be:

  • Tremors that are worse at rest
  • Moving slowly
  • Muscle stiffness
  • Problems doing tasks with the hands
  • Problems moving, such as taking smaller steps and shuffling
  • Problems doing activities of daily living, such as dressing
  • Fatigue
  • Pain
  • Sleep problems
  • Mood swings
  • Problems thinking
  • Perceiving things that are not there
  • Believing things that are not based in reality
  • Lightheadedness
  • Constipation
  • Problems with urine and bowel control


The doctor will ask about symptoms and past health. A physical exam will be done. Symptoms may be enough to make the diagnosis. There are no tests for PD.

Images may be taken to rule out other causes. Tests may be:


There is no cure. Treatment is aimed at managing symptoms.


Medicines that may be used to ease symptoms are:

  • Levodopa-carbidopa to treat tremors and problems moving
  • Dopamine agonists
  • Monoamine oxidase type B inhibitors
  • Anticholinergics
  • COMT inhibitors
  • Antivirals

Medicine may also be given to ease symptoms of depression.


Surgical choices are:

  • Deep brain stimulation (DBS)—implants a device to stimulate certain parts of the brain to ease problems with movement
  • Thalamotomy—destroys certain parts of the brain to improve severe tremors

Physical Therapy

Therapy can improve muscle tone, strength, balance, and movement.

Cognitive Behavioral Therapy

Cognitive behavioral therapy may ease symptoms and improve quality of life. It has a person examine their feelings and thought patterns, learn to interpret them, and apply coping methods to situations.


There are no current guidelines to prevent PD.


National Parkinson Foundation 

Parkinson's Disease Foundation 


Health Canada 

Parkinson Society Canada 


Burbulla LF, Song P, Mazulli JR. Dopamine oxidation mediates mitochondrial and lysosomal dysfunction in Parkinsons disease. Science. 2017;357(6357):1255-61.

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Managing Parkinson's. Parkinson’s Disease Foundation website. Available at: Accessed October 21, 2020.

Michels K, Dubaz O, et al. "Dance Therapy" as a psychotherapeutic movement intervention in Parkinson's disease. Complement Ther Med. 2018 Oct;40:248-252.

Parkinson's disease. American Association of Neurological Surgeons website. Available at: Accessed October 21, 2020.

Parkinson disease. EBSCO DynaMed website. Available at: Accessed October 21, 2020.

Parkinson's disease information page. National Institute of Neurological Disorders and Stroke website. Available at: Updated August 28, 2019. Accessed October 21, 2019.

2/24/2016 DynaMed Systematic Literature Surveillance Leung IH, Walton CC, Hallock H, et al. Cognitive training in Parkinson disease: a systematic review and meta-analysis. Neurology. 2015;85(21):1843-1851.

10/17/2016 DynaMed Systematic Literature Surveillance Ni M Signorile JF, et al. Comparative effect of power training and high-speed yoga on motor function in older patients with Parkinson disease. Arch Phys Med Rehabil. 2016 Mar;97(3):345-354.

Revision Information

  • Reviewer: EBSCO Medical Review Board Rimas Lukas, MD
  • Review Date: 09/2020
  • Update Date: 09/04/2020