Pseudobulbar palsy refers to a group of symptoms—including difficulty with chewing, swallowing, and speech, as well as inappropriate emotional outbursts—that accompany a variety of nervous system disorders.
Pseudobulbar palsy refers to a cluster of symptoms that can affect individuals suffering from a number of nervous system conditions, such as amyotrophic lateral sclerosis, Parkinson's disease, stroke, multiple sclerosis, or brain damage due to overly rapid correction of low blood sodium levels.
Causes and symptoms
Pseudobulbar palsy occurs when nervous system conditions cause degeneration of certain motor nuclei (nerve clusters responsible for movement) that exit the brain stem.
Patients with pseudobulbar palsy have progressive difficulty with activities that require the use of muscles in the head and neck that are controlled by particular cranial nerves. The first noticeable symptom is often slurred speech. Over time, speech, chewing, and swallowing become progressively more difficult, eventually becoming impossible. Sudden emotional outbursts, in which the patient spontaneously and without cause begins to laugh or cry, are also a characteristic of pseudobulbar palsy.
Diagnosis is usually made by noting the symptom cluster characteristic of pseudobulbar palsy. Diagnostic tests will be run to determine what underlying neurological disorder has led to the development of pseudobulbar palsy. In particular, neuroimaging (CT and MRI scans) can be used to diagnose many of the conditions that prompt the development of pseudobulbar palsy.
Neurologists usually care for patients with the kinds of conditions that include the symptoms of pseudobulbar palsy.
There are no cures for pseudobulbar palsy; the symptoms usually progress over the course of several years, leading to complete disability. Some medications may improve the emotional symptoms associated with pseudobulbar palsy; these include levodopa, amantadine, amitriptyline, and fluoxetine.
The prognosis for pseudobulbar palsy is quite poor. When the symptoms progress to disability, there is a high risk of choking and aspiration (breathing food or liquids into the lungs), which can lead to severe pneumonia and death. The conditions with which pseudobulbar palsy is associated also have a high risk of progression to death.
Friedman, Joseph. "Mood, Emotion, and Thought." In Textbook of Clinical Neurology, edited by Christopher G. Goetz. Philadelphia: W. B. Saunders Company, 2003.
Murray, T. Jock, and William Pryse-Phillips. "Amyotrophic Lateral Sclerosis." In Noble: Textbook of Primary Care Medicine, edited by John Noble, et al. St. Louis: W. B. Saunders Company, 2001.
Rosalyn Carson-DeWitt, MD