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 these 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 which contains these neurons.

There have been clusters of cases amongst 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.

• Muscle rigidity:
  • Stiffness
  • Difficulty bending arms or legs
• Posture may be unstable, stooped, or slumped over
• Movement difficulties:
  • Loss of balance
  • Gait (walking pattern) changes
  • Shuffling
  • Slow movements
  • Difficulty beginning to walk, difficulty initiating any voluntary movement
  • Small steps followed by the need to run to maintain balance
  • Freezing of movement when the movement is stopped, unable to resume movement
• Muscle aches and pains (myalgia)
• Muscle cramps and dystonia
• Shaking, tremors (varying degrees, may not be present):
  • May occur at rest or at any time
  • May become severe enough to interfere with activities
  • May be worse when tired, excited, or stressed
  • Finger-thumb rubbing (pill rolling tremor) may be present
• Changes in facial expression:
  • Reduced ability to show facial expressions, "mask" appearance
  • Staring
  • Eye movement abnormality (difficulty moving eyes up and down)
  • May be unable to close mouth
• Voice or speech changes:
  • Slow speaking
  • Low pitched voice
  • Monotone
  • Difficulty speaking
• Difficulty chewing or swallowing
• Loss of fine motor skills:
  • Difficulty writing, may be small and illegible
  • Difficulty eating
  • Difficulty with any activity that requires small movements
  • Frequent falls
• Mild decline in intellectual function (may occur)

• Depression
• Confusion
• Dementia

The health care provider may be able to diagnose secondary parkinsonism based on the patient's history, symptoms and physical examination. However, the symptoms may be difficult to assess, particularly in the elderly.

For example, the tremor may not appear when the person is sitting quietly with the arms in the lap. The posture changes may be similar to those caused by osteoporosis or other changes associated with aging. The lack of facial expression may be a sign of depression.

Examination may show increased muscle tone, tremors of the Parkinson's type and difficulty initiating or completing voluntary movements. Reflexes are usually normal.

Tests are not usually specific for secondary parkinsonism, but it may be used to confirm or rule out other disorders that may cause similar symptoms.

Treatment is aimed controlling symptoms. If the symptoms are mild, no treatment may be required.

If the condition is caused by a medication, the benefits of the medication should be weighed against the severity of symptoms and stopped or changed if they seem counterproductive.

Treatment of underlying conditions (such as stroke, infections) can reduce symptoms.

Medications may be used if symptoms interfere with the ability to perform daily activities. The medication, or dose, timing or combination of medications may need to be adjusted as symptoms change.

Many of the medications used to treat this condition can cause severe side effects, so monitoring and follow up by the health care provider are important. Secondary parkinsonism tend to be less responsive to medical therapy than Parkinson's disease.

Medications include:

• Amantadine or anticholinergic medications
• Levodopa/carbidopa
• Dopamine agonists

• Disability, varying degrees
• Difficulty swallowing (eating)
• Difficulty performing daily activities
• Injuries from falls
• Side effects of medications
• Debilitation and associated conditions:
  • Malnutrition
  • Aspiration
  • Deep vein thrombosis