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Secondary and Atypical Parkinsonism

By

Hector A. Gonzalez-Usigli

, MD, HE UMAE Centro Médico Nacional de Occidente

Last full review/revision May 2020| Content last modified May 2020
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Topic Resources

Secondary parkinsonism refers to a group of disorders that have features similar to those of Parkinson disease but have a different etiology. Atypical parkinsonism refers to a group of neurodegenerative disorders other than Parkinson disease that have some features of Parkinson disease but have some different clinical features and a different pathology. Diagnosis is by clinical evaluation and response to levodopa. Treatment is directed at the cause when possible.

In secondary parkinsonism, the mechanism is blockade of or interference with dopamine’s action in the basal ganglia.

Etiology of Secondary and Atypical Parkinsonism

The most common cause of secondary parkinsonism is

  • Use of drugs that decrease dopaminergic activity

These drugs include antipsychotics (eg, phenothiazine, thioxanthene, butyrophenone), antiemetics (eg, metoclopramide, prochlorperazine), and drugs that deplete dopamine (eg, tetrabenazine, reserpine).

Table
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Symptoms and Signs

Diagnosis

  • Clinical evaluation

  • Response to levodopa therapy

  • For differential diagnosis, sometimes neuroimaging

To differentiate Parkinson disease from secondary or atypical parkinsonism, clinicians note whether levodopa results in dramatic improvement, suggesting Parkinson disease.

Causes of parkinsonism can be identified by the following:

  • A thorough history, including occupational, drug, and family history

  • Evaluation for neurologic deficits characteristic of neurodegenerative disorders other than Parkinson disease

  • Neuroimaging when indicated

Deficits that suggest neurodegenerative disorders other than Parkinson disease include gaze palsies Conjugate Gaze Palsies A conjugate gaze palsy is inability to move both eyes together in a single horizontal (most commonly) or vertical direction. (See also Overview of Neuro-ophthalmologic and Cranial Nerve Disorders... read more , signs of corticospinal tract dysfunction (eg, hyperreflexia), myoclonus Myoclonus Myoclonus is a brief, shocklike contraction of a muscle or group of muscles. Diagnosis is clinical and sometimes confirmed by electromyographic testing. Treatment includes correction of reversible... read more , autonomic dysfunction Overview of the Autonomic Nervous System The autonomic nervous system regulates physiologic processes. Regulation occurs without conscious control, ie, autonomously. The 2 major divisions are the Sympathetic system Parasympathetic... read more Overview of the Autonomic Nervous System (if early or severe), cerebellar ataxia Cerebellar Disorders Cerebellar disorders have numerous causes, including congenital malformations, hereditary ataxias, and acquired conditions. Symptoms vary with the cause but typically include ataxia (impaired... read more , prominent dystonia Dystonias Dystonias are sustained involuntary muscle contractions of antagonistic muscle groups in the same body part, leading to sustained abnormal posturing or jerky, twisting, intermittent spasms that... read more , ideomotor apraxia (inability to mimic hand motions), early dementia Dementia Dementia is chronic, global, usually irreversible deterioration of cognition. Diagnosis is clinical; laboratory and imaging tests are usually used to identify treatable causes. Treatment is... read more , early falls, and confinement to a wheelchair.

Treatment

  • Treatment of the cause

  • Physical measures

The cause of secondary parkinsonism is corrected or treated if possible, sometimes resulting in clinical improvement or disappearance of symptoms.

Drugs used to treat Parkinson disease are often ineffective or have only transient benefit. But amantadine or an anticholinergic drug (eg, benztropine) may ameliorate parkinsonism secondary to use of antipsychotic drugs. However, because these drugs may worsen cognitive decline and possibly increase tau pathology and neurodegeneration, their use should be limited (1 Treatment references Secondary parkinsonism refers to a group of disorders that have features similar to those of Parkinson disease but have a different etiology. Atypical parkinsonism refers to a group of neurodegenerative... read more , 2 Treatment references Secondary parkinsonism refers to a group of disorders that have features similar to those of Parkinson disease but have a different etiology. Atypical parkinsonism refers to a group of neurodegenerative... read more ).

Physical measures to maintain mobility and independence are useful (as for Parkinson disease). Maximizing activity is a goal. Patients should increase daily activities to the greatest extent possible. If they cannot, physical or occupational therapy, which may involve a regular exercise program, may help condition them physically. Therapists may teach patients adaptive strategies, help them make appropriate adaptations in the home (eg, installing grab bars to reduce the risk of falls), and recommend adaptive devices that may be useful.

Good nutrition is essential.

Treatment references

  • 1. Yoshiyama Y, Kojima A, Itoh K, Uchiyama T, Arai K: Anticholinergics boost the pathological process of neurodegeneration with increased inflammation in a tauopathy mouse model. Neurobiol Dis 2012 45 (1):329-336, 2012. doi: 10.1016/j.nbd.2011.08.017.

  • 2. Yoshiyama Y, Kojima A, Itoh K, et al: Does anticholinergic activity affect neuropathology? Implication of neuroinflammation in Alzheimer's disease. Neurodegener Dis 15 (3):140-148, 2015. doi: 10.1159/000381484.

Key Points

  • Parkinsonism can be caused by drugs, toxins, neurodegenerative disorders, and other disorders that affect the brain (eg, stroke, tumor, infection, trauma, hypoparathyroidism).

  • Suspect parkinsonism based on the clinical evaluation and differentiate it from Parkinson disease by the lack of response to levodopa; neuroimaging may be needed.

  • Check for deficits that suggest a neurodegenerative disorder other than Parkinson disease.

  • Correct or treat the cause if possible, and recommend physical measures to maintain mobility.

Drugs Mentioned In This Article

Drug Name Select Trade
COMPRO
REGLAN
COGENTIN
No US brand name
DEMEROL
Levodopa
LITHOBID
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