Secondary Parkinsonism

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

The term "parkinsonism" refers to any condition that involves the types of movement changes seen in Parkinson's disease.

Causes

Parkinson's disease is one of the most common nervous system disorders affecting the elderly.

Parkinson's disease occurs when the nerve cells in the brain that make a checmical called dopamine are slowly destroyed. Dopamine helps control muscle movement. Without dopamine, the nerve cells in that part of the brain cannot properly send messages. This leads to the loss of muscle function. The damage gets worse with time. Exactly why these brain cells waste away is unknown.

Secondary parkinsonism may be caused by health problems, including:

• Encephalitis
• Meningitis
• Stroke
• Diffuse Lewy body disease
• Multiple system atrophy
• Progressive supranuclear palsy

Certain medications can cause secondary parkinsonism, including:

• Antipsychotics (haloperidol)
• Metoclopramide
• Phenothiazine medications

Other causes of secondary parkinsonism include:

• Brain damage caused by anesthesia drugs (such as during surgery)
• Carbon monoxide poisoning
• Mercury poisoning and other chemical poisonings
• Overdoses of narcotics

There have been cases of secondary parkinsonism among IV drug users who injected a substance called MPTP, which can be produced when making a form of heroin. These cases are rare and have mostly affected long-term drug users.

Symptoms

Common symptoms include:

• Decrease in facial expressions
• Difficulty starting and controlling movement
• Loss or weakness of movement (paralysis)
• Soft voice
• Stiffness of the trunk, arms, or legs
• Tremor

Confusion and memory loss may be more likely in secondary parkinsonism. This is because the diseases that cause secondary parkinsonism often lead to dementia.

For a more detailed description of symptoms, see Parkinson's disease.

Exams and Tests

The health care provider may be able to diagnose secondary parkinsonism after performing a physical exam and asking questions about your medical history and symptoms. However, the symptoms may be difficult to assess, particularly in the elderly.

Examination may show:

• Difficulty starting or stopping voluntary movements
• Increased muscle tone
• Problems with posture
• Slow, shuffling walk
• Tremors

Reflexes are usually normal.

Tests may be used to confirm or rule out other disorders that can cause similar symptoms.

Treatment

If the condition is caused by a medication, your doctor may recommend changing or stopping the medicine. However, the benefits of the medication should be weighed against the severity of symptoms. Medications should be stopped or changed if the risks outweigh the benefits.

Treating underlying conditions such as stroke or infections can reduce symptoms.

If your symptoms make it hard to do everyday activities, your doctor may recommend medication. Many of the medications used to treat this condition can cause severe side effects. It is important that you see your doctor for check-ups. Secondary parkinsonism tends to be less responsive to medical therapy than Parkinson's disease. However, medications are worth trying if the cause of the condition is not treatable.

For a more detailed description of treatment, see Parkinson's disease.

Outlook (Prognosis)

Secondary parkinsonism caused by antipsychotics or other medications is usually reversible if identified soon enough. However, it may not be reversible if it is caused by:

• Drug-related brain damage
• Infections
• Toxins

All other causes are not reversible and tend to get worse over time.

Possible Complications

• Difficulty performing daily activities
• Difficulty swallowing (eating)
• Disability (varying degrees)
• Injuries from falls
• Side effects of medications

Side effects from loss of strength (debilitation):

• Aspiration
• Deep vein thrombosis
• Malnutrition

When to Contact a Medical Professional

Call your health care provider if:

Symptoms of secondary parkinsonism develop, come back, or get worse

• New symptoms appear, including:
• Changes in alertness, behavior, or mood
• Delusional behavior
• Dizziness
• Hallucinations
• Involuntary movements
• Loss of mental functions
• Nausea or vomiting
• Possible side effects of medications
• Severe confusion or disorientation

Discuss the situation with your health care provider if you are unable to care for the person at home (after treatment begins).

Prevention

Treating conditions that cause secondary parkinsonism may decrease the risk.

People with conditions that require long-term use of antipsychotics should be carefully monitored to prevent the development of secondary parkinsonism. Newer antipsychotic medications are less likely to cause secondary parkinsonism.

Source: http://www.nlm.nih.gov/medlineplus/ency/article/000759.htm