Parkinsonism is a syndrome (collection of symptoms and signs) characterized by bradykinesia (slowed movements), tremors, loss of balance, and stiffness. The most common type of parkinsonism is Parkinson’s disease, which accounts for about 80 percent of cases. Other types of parkinsonism include drug-induced parkinsonism, multiple system atrophy, progressive supranuclear palsy, vascular parkinsonism, dementia with Lewy bodies, and corticobasal degeneration.

Parkinson’s disease and other types of parkinsonism are chronic diseases of the brain and spinal cord, also referred to as the central nervous system (CNS). Parkinson's can be treated, but there is no cure. Symptoms vary among people with Parkinson’s, but motor (movement) and cognitive (brain-related) problems are among the most common. Parkinson’s symptoms worsen over time, gradually becoming debilitating and causing severe disability. Parkinson’s is not fatal, and on average, people with Parkinson’s and people without it have similar life spans.

What Is Parkinson’s?

Deep inside the brain, regions called the basal ganglia and substantia nigra work together to ensure that the body moves smoothly. The substantia nigra produces a neurotransmitter — a chemical that helps nerves communicate — called dopamine.

The messages that the brain sends to the muscles (to get them to move) pass through the ganglia with the help of dopamine. In parkinsonism, cells in the substantia nigra gradually stop producing dopamine and die off. With too little dopamine, the basal ganglia cannot facilitate movement as well as it can when dopamine is at normal levels. Researchers believe parkinsonian symptoms begin when the level of dopamine falls to about half of normal levels.

When this occurs, other parts of the brain try to compensate for the lack of dopamine, and this causes more dysfunction.

What Causes Parkinson’s?

Different types of parkinsonism can have different causes. Some people have a strong family history of Parkinson’s, and genetics play a role. Others develop parkinsonism after taking certain psychiatric, antinausea, or recreational drugs. For most people, Parkinson’s is most likely caused by a combination of inherited predisposition and environmental risk factors such as head injuries and exposure to radiation or toxins.

Read more about causes of Parkinson’s.

The History of Parkinson’s

As early as 600 B.C.E., medical texts from India described the symptoms of Parkinson’s disease. Doctors who practiced Ayurveda (traditional Indian medicine) prescribed powdered velvet-bean seeds, which may have been effective: The bean contains a small amount of levodopa, the most common treatment for Parkinson’s today. In Ayurveda, Parkinson’s is called “kampavata,” from the Sanskrit “kampa,” meaning “shaking,” and “vata,” meaning “lack of muscular movement.” In ancient Greece, the physician Galen described cases of “shaking palsy” as early as 175 C.E.

In 1817, English doctor James Parkinson published "An Essay on the Shaking Palsy," in which he described cases of movement disorders that he treated in his practice and witnessed among Londoners. Parkinson recommended bloodletting and inducing blisters on the neck as treatment.

From 1868 to 1881, French neurologist Jean-Martin Charcot completed several studies that helped define the condition. Charcot also promoted naming the disease after Dr. Parkinson. Charcot and his team published papers recommending two plant-based drugs, belladonna and hyoscyamine, as treatments for parkinsonism. These 19th-century medications are in the anticholinergic and muscarinic antagonist classes of drugs, respectively; other drugs in these classes are still used to treat Parkinson’s.

German neurologist Frederic Lewy discovered abnormal “spherical inclusions” in 1912 when conducting autopsies of people who died with Parkinson’s disease. Now known as Lewy bodies, these deposits of alpha-synuclein (aS) protein are understood to be one of the most common causes of dementia in people with parkinsonism.

Starting in the 1950s, researchers began to learn more about the neurotransmitter dopamine, where it is made in the brain, and its role in motor and cognitive functions. This research led to the discovery that Parkinson’s was caused by dopamine loss. This led to the realization that levodopa increases dopamine, which made it a promising treatment for Parkinson’s. Levodopa was first given to people with Parkinson’s in 1961 and immediately proved extremely effective. Levodopa remains the gold standard of Parkinson’s treatment.

Since the 1990s, scientists have found several genes associated with the development of Parkinson’s. In 2002, the U.S. Food and Drug Administration (FDA) approved deep brain stimulation, a surgical procedure that uses electrical stimulation and helps improve movement symptoms such as tremor. Experiments that transplant stem cells to produce dopamine have been promising, and clinical trials are underway to test the safety and effectiveness of this treatment.

How Common Is Parkinson’s?

Approximately 10 million people around the world and more than 1 million in the United States have Parkinson’s disease. Close to 1 percent of the population over age 60 will develop Parkinson’s. About 60,000 new cases are diagnosed in the U.S. each year. Parkinson’s is typically diagnosed in people between the ages of 40 and 70, with the majority diagnosed in their 70s. Only about 4 percent of Parkinson’s disease cases are diagnosed before age 50. In rare instances, Parkinson’s has been diagnosed in people as young as 18.

How Does Parkinson’s Progress?

Everyone diagnosed with Parkinson’s disease experiences disease progression. Some types of parkinsonism and some individuals progress more quickly than others. People with Parkinson’s can experience different symptoms at different intensities, and earlier or later in the course of the disease. There are five stages of Parkinson’s that describe the most typical pattern of progression, from mild motor symptoms that gradually grow more severe and cause increasing levels of disability. Some people with Parkinson’s experience cognitive symptoms that also worsen over time.

Find Your Team

MyParkinsonsTeam is the social network for people with Parkinson’s disease and their loved ones. On MyParkinsonsTeam, more than 105,000 members come together to ask questions, give advice, and share their stories with others who understand life with Parkinson’s.

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