Symptom Management

Reining in Pseudobulbar Affect

By MSF Staff and reviewed by the the Multiple Sclerosis Foundation Medical Advisory Board

When coping with a chronic and unpredictable disease such as MS, it is common to experience a wide range of emotions. However, people with MS who have a condition known as pseudobulbar affect (PBA) can be caught off guard by episodes of uncontrollable laughing and/or crying that may be inappropriate, unrelated to the situation at hand, or not expressing their actual mood.

PBA is also known by these other terms:  involuntary emotional expression disorder, emotional lability, emotional incontinence, and pathological laughing and crying. It is associated with neurologic disorders that may include, but are not limited to MS, amyotrophic lateral sclerosis, dementias (including Alzheimer's disease), Parkinson's disease, stroke, and traumatic brain injury. It is estimated that about 10 percent of people with MS suffer from PBA, but because the condition is easily overlooked or misdiagnosed, the number of cases may be much higher.

Additionally, data suggest that many people (about 40 percent in one study) experiencing symptoms common to PBA do not discuss the problem with their doctors. This may be due to embarrassment as well as an incorrect belief that PBA is a psychological illness and not a disease symptom. 

If you think you might have PBA, it is important to discuss the details with your doctor because the condition can be treated. In late 2010, the US Federal Drug Administration approved Nuedexta™, the first treatment for PBA. 

Triggers, Causes and Diagnosis

Outbursts associated with PBA may occur spontaneously or in response to certain situations, such as questions or events. Regardless of the situation, the outbursts are not true indications of the person’s internal emotional state.

The exact cause of PBA is not understood but it is generally accepted that PBA may occur when disease or injury damages the area of the brain that controls normal expression of emotion. This damage can disrupt brain signaling causing a “short circuit,” triggering episodes of involuntary emotional expression. It is easy to imagine how this might happen with a disease such as MS, which has the potential to disrupt nerve transmissions throughout the body.

Only a trained medical professional can clinically diagnose PBA. Neurologists and psychiatrists are the physicians who most often specialize in diagnosing and treating the disorder. It is important to receive an accurate diagnosis as PBA is sometimes misconstrued as depression or some other psychiatric condition.

Though people who have PBA can experience a range of emotions related to coping with the disorder, including anger and frustration, they do not ordinarily have thoughts of helplessness, hopelessness or guilt; nor do they typically experience problems or changes in sleep or appetite – characteristics that often accompany depression.

Getting Help

For many people and families dealing with PBA, the disorder's symptoms can be stressful and embarrassing enough to cause withdrawal from social situations. The associated stress of PBA can affect the health of everyone affected. Establishing open, honest communications among family members and with your medical providers is the first step towards treatment.

Once your doctor has given you a diagnosis of PBA, you may be a candidate for NuedextaTM. This oral medication (in capsule form, taken twice daily) is a combination of the generic drug quinidine, which prevents heart arrhythmia, and the cough suppressant dextromethorphan. 

The most common side effects of Nuedexta include diarrhea, dizziness, cough, vomiting, weakness, swelling of feet and ankles, urinary tract infection, flu, elevated liver enzymes, and flatulence. Nuedexta can interact with other medications, causing significant changes in how those medications or Nuedexta may affect you, so it is important to tell your doctor all the medicines and supplements you take. 

If you think you may be a candidate for this medication, talk with your doctor about your options. In the past, tricyclic anti-depressants (such as amitriptyline and nortriptylene) and selective serotonin reuptake inhibitors (such as Prozac®, Paxil®, Zoloft®, Celexa®, and Lexapro®) have been used to treat PBA, although with only modest success. 

By reducing the frequency and severity of emotional episodes, you may discover a renewed interest in social activities and the desire to participate.

(Last reviewed 7/2011)