Secondary parkinsonism

Definition

Secondary parkinsonism is similar to Parkinson's disease, but is caused by certain medicines, an different nervous system disorder, or another illness.

Alternative Names

Causes

Parkinson's disease is one of the most common neurologic disorders of the elderly. The term "parkinsonism" refers to any condition that causes any combination of the types of movement abnormalities seen in Parkinson's disease by damaging or destroying dopamine neurons in a certain area of the brain.

Secondary parkinsonism may be caused by disorders such as a stroke, encephalitis, or meningitis. Other neurodegenerative disorders such as progressive supranuclear palsy, corticobasal degeneration, and multiple systems atrophy can also damage the dopamine neurons and produce this condition.

Medications including antipsychotics such as haloperidol, metoclopramide, and phenothiazine medications are another common cause of secondary parkinsonism.

Less frequently, exposure to overdoses of narcotics or brain damage caused by anesthesia agents (such as during surgery); exposure to toxins, and carbon monoxide poisoning can cause secondary parkinsonism if they damage the brain area that contains the dopamine neurons.

There have been clusters of cases among intravenous drug users who injected a substance called MPTP, which is a byproduct of an improper technique for synthesizing a form of synthetic heroin (fentanyl derivative). These cases are rare and have affected primarily long-term drug users.

Secondary parkinsonism caused by medications like antipsychotics is usually reversible. If it is caused by toxins, infections, drug-related brain damage, or certain other disorders it may or may not be reversible.

Symptoms of parkinsonism may include stiffness of the trunk, arms, or legs, a decrease in facial expression, soft voice, tremor, some forms of paralysis, and certain problems with control of movement.

Although cognitive dysfunction is not a major feature of Parkinson's disease, it may be more prominent in secondary parkinsonism as the diseases that cause secondary parkinsonism more commonly also result in dementia.

References

U.S. Food and Drug Administration. FDA Approves Neupro Patch for Treatment of Early Parkinson's Disease. Rockville, MD: National Press Office; May 9, 2007. Release P07-84.

Goetz, CG. Textbook of Clinical Neurology. 2nd ed. St. Louis, Mo: WB Saunders; 2003: 713-720.

Noble J. Textbook of Primary Care Medicine. 3rd ed. St. Louis, Mo: Mosby; 2001:1612-1618.