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Disease Profile

Parkinson disease

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Parkinson's disease; Paralysis agitans; Shaking palsy;


Parkinson disease (PD) is a neurologic disease that affects the movement. The four main symptoms are tremors of the hands, arms, legs, jaw, or head, specially at rest; rigidity, or stiffness; bradykinesia, or slow movement; and postural instability or inability to find balance. The symptoms start slowly, but progress over time, impairing everyday activities such as walking, talking, or completing simple tasks. Other symptoms may include emotional problems, trouble swallowing and speaking; urinary problems or constipation; skin problems; sleep problems, low blood pressure when standing up from sitting or lying down (postural hypotension), and inexpressive face. Some people will loose their mental abilities (dementia).[1][2][3]

Parkinson disease affects several regions of the brain, especially a region known as "substantia nigra" that helps controlling balance and movement. Most cases of PD are sporadic (with no family history), and with onset around 60 years of age; onset before age 20 years is considered to be juvenile-onset Parkinson disease, and after age 50 years is considered late-onset Parkinson disease. However, in some families, there are several cases of Parkinson disease. Familial cases of Parkinson disease, and maybe some sporadic cases, can be caused by changes (mutations) in several genes, such as:[1][2][4] 

  • Mutations in the SNCA (PARK1), LRRK2 (PARK8), and VPS35 (PARK17) genes are inherited in an autosomal dominant manner.
  • Mutations in genes PARK2PARK7, and PINK1 (PARK6) appear to be inherited in a recessive manner.
  • Very rare mutations in the TAF1 gene cause Parkinson disease with X-linked inheritance.
  • Mutations in some genes, including GBA and UCHL1 (PARK 5), do not seem to cause Parkinson disease, but to increase the risk of developing the disease in some families.

Autosomal recessive PD have earlier onset than autosomal dominant PD. Some studies suggest that these genes are also involved in early-onset or juvenile PD. However, inheriting a mutation does not always mean that a person will have Parkinson's disease, because there may be other genes and environmental factors determining who will develop Parkinson disease.[2]

Treatment is usually based on a medication known as levodopa. Other medication includes bromocriptine, pramipexole, ropinirole, amantadine, rasagiline and safinamide. Deep brain stimulation (DBS) a surgical procedure where electrodes are implanted into the brain may be useful for some people.[3][2] Prognosis varies, and while some people become disabled, others will have only minor movement problems.[2] Studies have shown that people with PD who have cognitive impairment, postural hypotension, and sleep problems may have a more rapid progression of the disease.[5]


A number of disorders can cause symptoms similar to those of Parkinson disease. People with symptoms that resemble Parkinson disease but that result from other causes are sometimes said to have parkinsonism. Some of these disorders are listed below.[2]

  • Postencephalitic parkinsonism
  • Drug-induced parkinsonism
  • Toxin-induced parkinsonism
  • Arteriosclerotic parkinsonism
  • Parkinsonismdementia complex of Guam
  • Post-traumatic parkinsonism
  • Essential tremor
  • Normal pressure hydrocephalus
  • Progressive supranuclear palsy
  • Corticobasal degeneration
  • Multiple system atrophy
  • Dementia with Lewy bodies 

More information on each of these conditions is available in the National Institute of Neurological Disorders and Stroke (NINDS) publication, Parkinson's Disease: Hope Through Research. 

Parkinsonian symptoms may also appear in patients with other, clearly distinct neurological disorders such as Wilson disease, Huntington disease, Alzheimer disease, spinocerebellar ataxias, and Creutzfeldt-Jakob disease. Each of these disorders has specific features that help to distinguish them from Parkinson disease.[2]

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
5%-29% of people have these symptoms
Abnormal autonomic nervous system physiology
Sensory hallucination

[ more ]

Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance
Slow movements
Slowness of movements

[ more ]

Dementia, progressive
Progressive dementia

[ more ]

Difficulty articulating speech
Poor swallowing
Swallowing difficulties
Swallowing difficulty

[ more ]

Insidious onset
Gradual onset
Lewy bodies
Mask-like facies
Expressionless face
Lack of facial expression
Mask-like facial appearance

[ more ]

Neuronal loss in central nervous system
Loss of brain cells
Personality changes
Personality change
Postural instability
Balance impairment
Worsens with time
Resting tremor
Tremor at rest
Muscle rigidity
Short stepped shuffling gait
Short stepped shuffling walk
Sleep disturbance
Difficulty sleeping
Trouble sleeping

[ more ]

No previous family history
Substantia nigra gliosis
Urinary urgency
Overactive bladder
Weak voice
Soft voice


Parkinson disease occurs when the nerve cells in the brain that make dopamine, a chemical messenger which transmits signals within the brain to produce smooth physical movements, are slowly destroyed. Without dopamine, the nerve cells in the part of the brain known as the substantia nigra cannot properly send messages. This leads to progressive loss of muscle function. Exactly why these brain cells waste away is unknown.[2][6] Recent studies have shown that people with Parkinson disease also experience damage to the nerve endings that produce the neurotransmitter norepinephrine. Norepinephrine, which is closely related to dopamine, is the main chemical messenger of the sympathetic nervous system, the part of the nervous system that controls the automatic functions of the body, including pulse and blood pressure. The loss of norepinephrine may explain some of the non-motor features seen in Parkinson disease, including fatigue and problems with blood pressure regulation.[2] 

More detailed information about the cause of Parkinson disease is available through an information page developed by the National Institute of Neurological Disorders and Stroke (NINDS). Click here to view this information.


There are currently no blood or laboratory tests that have been proven to help diagnose sporadic cases of Parkinson disease. The diagnosis is generally made after careful evaluation of medical history, current symptoms, and exclusion of other conditions.[2] The clinical findings of tremor, rigidity, and bradykinesia are highly suggestive of Parkinson disease. The genetic cause of some forms of Parkinson disease has been identified. In those cases, genetic testing may be utilized to identify affected family members.[4]


The resources below provide information about treatment options for this condition. If you have questions about which treatment is right for you, talk to your healthcare professional.

Management Guidelines

  • The National Guideline Clearinghouse (NGC) is a public resource for evidence-based clinical practice guidelines. The NGC was originally created by the Agency for Healthcare Research and Quality (AHRQ) in partnership with the American Medical Association and the American Association of Health Plans.

    FDA-Approved Treatments

    The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.


    Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

    Organizations Supporting this Disease

      Organizations Providing General Support

        Learn more

        These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

        Where to Start

        • The Genetic Alliance is an international coalition comprised of more than 600 advocacy, research and health care organizations representing millions of individuals with genetic conditions. Click on the link to view information on this topic.
        • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
        • Genetics Home Reference (GHR) contains information on Parkinson disease. This website is maintained by the National Library of Medicine.
        • The Merck Manuals Online Medical Library provides information on this condition for patients and caregivers.
        • The National Human Genome Research Institute's (NHGRI) website has an information page on this topic. NHGRI is part of the National Institutes of Health and supports research on the structure and function of the human genome and its role in health and disease.
        • The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.
        • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

          In-Depth Information

          • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
          • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
          • MeSH® (Medical Subject Headings) is a terminology tool used by the National Library of Medicine. Click on the link to view information on this topic.
          • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
          • PubMed is a searchable database of medical literature and lists journal articles that discuss Parkinson disease. Click on the link to view a sample search on this topic.


            1. Learning about Parkinson Disease. National Human Genome Research Institute. March 14, 2014; https://www.genome.gov/10001217.
            2. Parkinson's Disease: Hope Through Research. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/disorders/parkinsons_disease/detail_parkinsons_disease.htm#127443159.
            3. Parkinson's disease. WebMD. https://www.webmd.com/parkinsons-disease/tc/parkinsons-disease-topic-overview#1.
            4. Pankratz ND, Wojcieszek J & Foroud T. Parkinson Disease Overview. GeneReviews. 2015; https://www.ncbi.nlm.nih.gov/books/NBK1223/.
            5. Barclay LL. Predicting Prognosis in Parkinson Disease. Medscape Reference. September 4, 2015; https://www.medscape.com/viewarticle/850159.
            6. Parkinson’s disease. MedlinePlus. May 6, 2011; https://www.nlm.nih.gov/medlineplus/ency/article/000755.htm. Accessed 10/3/2011.
            7. Parkinson disease. Genetics Home Reference (GHR). July 2007; https://ghr.nlm.nih.gov/condition/parkinson-disease. Accessed 10/3/2011.

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