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(Secondary Parkinsonism; Atypical Parkinsonism)


Hector A. Gonzalez-Usigli

, MD, HE UMAE Centro Médico Nacional de Occidente

Last full review/revision Sep 2020| Content last modified Sep 2020
Click here for the Professional Version

Parkinsonism refers to symptoms of Parkinson disease (such as slow movements and tremors) that are caused by another condition.

  • Parkinsonism is caused by brain disorders, brain injuries, or certain drugs and toxins.

  • People with parkinsonism, like those with Parkinson disease, have tremors that occur when muscles are relaxed, stiff muscles, slow movements, and problems with balance and walking.

  • Doctors try to identify the cause of parkinsonism by asking about conditions known to cause it and by using brain imaging to look for a possible cause.

  • The cause is treated if possible, drugs may be used to relieve symptoms, and general measures (such as simplifying daily tasks) may help people function better.

Causes of Parkinsonism

The most common cause of parkinsonism is

  • Use of drugs that block or interfere with dopamine’s action

Certain drugs and toxins interfere with or block the action of dopamine and other chemical messengers that help nerve cells communicate with each other (neurotransmitters). For example, antipsychotic drugs, used to treat paranoia and schizophrenia, block dopamine’s action. Dopamine is a key neurotransmitter in the basal ganglia (collections of nerve cells located deep within the brain), which help smooth out muscle movements.

Various other conditions can cause parkinsonism:

Parkinsonism caused by degenerative disorders of the brain is called atypical parkinsonism.

Symptoms of Parkinsonism

Parkinsonism causes the same symptoms as Parkinson disease. They include

  • A tremor that occurs in one hand while the muscles are relaxed (a resting tremor)

  • Stiff muscles

  • Slow movements

  • Difficulty maintaining balance and walking

The disorders that cause parkinsonism may also cause other symptoms or variations of parkinsonian symptoms.

Some symptoms may indicate the cause is not Parkinson disease. They include

  • Prominent memory loss that occurs during the first year of the disorder (indicating dementia)

  • Symptoms of parkinsonism on only one side of the body (often due to certain brain tumors or corticobasal ganglionic degeneration)

  • Low blood pressure, difficulty swallowing, constipation, and urinary problems (sometimes due to multiple system atrophy)

  • Falls and confinement to a wheelchair within the first months or years of a disorder

  • Abnormalities in eye movements

  • Hallucinations and visual-spatial problems (such as difficulty finding rooms at home or parking a car) that develop early in the disorder

  • Symptoms that do not lessen in response to treatment with levodopa

  • Inability to express or understand spoken or written language (aphasia), inability to do simple skilled tasks (apraxia), and inability to associate objects with their usual role or function (agnosia) due to corticobasal ganglionic degeneration

In corticobasal ganglionic degeneration, the cerebral cortex (the part of the brain that contains most of the nerve cells) and the basal ganglia deteriorate progressively. Symptoms usually begin after age 60.

People with corticobasal ganglionic degeneration have stiff muscles that affect one side of the body more than the other. As the disorder progresses, moving their limbs becomes increasingly difficult. Coordination and balance are poor, muscle twitch, and swallowing becomes difficult. Thinking is impaired, and people have difficulty finding, saying, and understanding words. Many people lose control of one hand (on the more affected side)—called alien hand syndrome. The hand may move on its own. For example, it may spontaneously open or make a fist.

Diagnosis of Parkinsonism

  • A doctor's evaluation

  • Usually brain imaging

  • Use of levodopa to see whether it helps

Doctors ask about previous disorders, exposure to toxins, and use of drugs that could cause parkinsonism.

Brain imaging, such as computed tomography (CT) or magnetic resonance imaging (MRI), is usually done to look for a structural disorder that may be causing the symptoms.

If the diagnosis is unclear, doctors may give the person levodopa (a drug used to treat Parkinson disease) to rule out Parkinson disease. If the drug results in clear improvement, Parkinson disease is the likely cause.

Treatment of Parkinsonism

  • Treatment of the cause if possible

  • Sometimes drugs to help relieve symptoms

  • General measures, such as staying as active as possible

The cause of parkinsonism is corrected or treated if possible. If a drug is the cause, stopping the drug may cure the disorder. Symptoms may lessen or disappear if the underlying disorder can be treated.

The drugs used to treat Parkinson disease (such as levodopa) are often not effective in people with parkinsonism but can sometimes result in temporary improvement.

If an antipsychotic drug is causing bothersome parkinsonian symptoms and an antipsychotic drug needs to be taken indefinitely, doctors substitute another antipsychotic drug if possible. However, if the drug cannot be changed, amantadine or a drug with anticholinergic effects, such as benztropine, may relieve symptoms.

The same general measures used to help people with Parkinson disease maintain mobility and independence are useful. For example, people should

  • Remain as active as possible

  • Simplify daily tasks

  • Use assistive devices as needed

  • Take measures to make the home safe (such as removing throw rugs to prevent tripping)

Physical therapists and occupational therapists can help people implement these measures.

Good nutrition is also important.

Drugs Mentioned In This Article

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Test your knowledge

Agnosia is loss of the ability to identify objects using one or more of the senses. Symptoms of agnosia vary depending on which areas of the brain are damaged. When a person cannot identify a telephone when hearing it ring, which of the following lobes of the brain is most likely damaged?
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