Pseudobulbar affect (PBA) is a neurological condition that is characterized by sudden, uncontrollable expressions of laughter or crying. This type of emotional behavior is difficult to control voluntarily and can be extremely distressing to those who experience it.
Nuedexta® (dextromethorphan hydrobromide and quinidine sulfate) is the only FDA-approved treatment specifically for PBA at this time. Some doctors may prescribe certain antidepressant medications, typically at a lower dose than when used for depression. While medications may help to manage the symptoms of PBA, they do not cure its underlying cause.
Pseudobulbar affect (PBA) is a neurological condition (or phenomenon) that may occur in a small number of people with MS. It is characterized by sudden, uncontrollable expressions of laughter or crying. Although there may be a minor trigger for the laughing or crying, the response is exaggerated and is disproportionate to the apparent trigger.
PBA is equally common among men and women and occurs in other chronic, neurological conditions such as traumatic brain injuries and amyotrophic lateral sclerosis (ALS). This type of emotional behavior is difficult to control voluntarily. It can be extremely distressing as well as embarrassing to those who experience it. With more education, people with MS will know to consult their neurologist if they experience any of its symptoms.
PBA is distinguished from depression by its sudden emotional reactivity – and one might think of it as the editor or the controller of your emotions is missing. Though depression and PBA both appear to result from the disease process of MS itself, PBA is specifically related to a certain set of behaviors, such as sudden and inappropriate laughing or crying. You could have MS with depression and not experience PBA, or you could have PBA but not have depression, or you could experience both.
PBA is caused by a disruption of nerve impulses within the central nervous system, and this alteration in signals causes a dysregulation of mood control. “Bulbar” refers to a bulb-shaped area at the base of the brain (brainstem), now more commonly known as the medulla oblongata.
Among other functions, this area of the brain plays a role in emotional reactions. With “pseudo” bulbar affect, the dysfunction appears to be a problem in the bulbar area, but it actually originates in the fiber tracts going to the medulla oblongata.
In 2010, Nuedexta® (dextromethorphan hydrobromide and quinidine sulfate) was approved by the Food and Drug Administration (FDA) to treat PBA episodes in MS. Nuedexta is the first and only approved treatment for PBA at this time.
Some doctors advocate using certain antidepressant medications, including the SSRIs (selective serotonin reuptake inhibitors), such as Celexa® (citalopram) and Zoloft® (sertraline). Although their exact course of action is not clear, they appear to be effective for many. These antidepressants are typically administered at a lower dose than for depression. While these medications may well help to manage the symptoms of PBA, they do not cure its underlying cause.
If you experience PBA, hope is in sight, as doctors and researchers are learning more about this symptom. The Center for Neurologic Study Emotional Lability Scale is a good screening tool available for PBA. You can complete it at your MS neurologist’s office. If you have PBA, your MS neurologist will determine which medication is best for you.
Updated in August 2023 by Dr. Barry Hendin, MSAA Chief Medical Officer
Original content by Dr. Miriam Franco MSW, PsyD, MSCS
