Pseudobulbar affect

Last updated Aug. 17, 2023, by Susie Strachan
Fact-checked by Patricia Silva, PhD

Pseudobulbar affect (PBA) is a neurological condition characterized by bouts of sudden, involuntary, exaggerated, or inappropriate laughter or crying, which often do not reflect the real emotional state of the person.

The condition can occur in people with amyotrophic lateral sclerosis (ALS), particularly among those with the bulbar onset form of the disease — that is, patients in whom the first disease symptoms affect the muscles around the jaw and throat.

PBA can cause problems for people living with ALS. Some people experience feelings of embarrassment after PBA episodes, which may lead to social isolation, while mental health issues such as depression and anxiety can be amplified by the condition.

Treatment in the form of medication is available, and self-management coping strategies can also help people with PBA.

PBA causes

PBA is linked to neurological diseases or damage, including conditions such as ALS, Alzheimer’s disease, traumatic brain injury, and stroke. It is estimated that around 2 to 7 million people in the U.S. have PBA.

The condition is not a mental health issue, although it is often mistaken for anxiety or depression.

The exact cause of PBA is not completely known, but it is thought to be related to a disruption in the brain’s circuits that regulate the expression of emotions.

Brain MRI scans of people with ALS have tied their inability to regulate emotional expression to changes in the frontal area of the brain, including alterations of the fronto-tempo-parietal-cerebellar circuits. PBA also has been linked to an abnormality of chemical messengers called neurotransmitters that regulate the expression of emotions.

The rate of PBA among people with ALS is estimated to be around 38.5%, according to a 2022 review study — a value higher than in other neurodegenerative diseases such as Parkinson’s disease, Alzheimer’s disease, and other forms of dementia.

PBA symptoms

PBA symptoms can include:

• uncontrollable crying and laughing
• laughing and crying at the same time
• no apparent reason for the outburst
• episodes that are not tied to the emotion or social situation that the person is feeling or experiencing.

Episodes tend to be brief, but intense.

PBA symptoms can cause social embarrassment and anxiety, due to the lack of control a person can feel.

PBA differs from the symptoms of depression. For people with depression:

• symptoms are linked to the emotions and mental state that a person is feeling
• symptoms can be easier to gain control of, particularly once an emotional trigger has been identified
• laughter isn’t usually a symptom.

Nonetheless, a person with ALS can have both depression and PBA. PBA is not tied to other symptoms of ALS such as muscle weakness.

PBA diagnosis

PBA symptoms are often attributed to psychiatric or mood disorders, such as depression or bipolar disorder, rather than neurological causes.

However, depression is linked to a person’s mental health, and can often include periods of ongoing sadness, anxiety, and mental fatigue. The crying episodes in PBA are brief and not necessarily related to sadness. Other symptoms of depression, such as appetite loss or sleep disturbances, are usually absent in people with ALS who have PBA.

PBA is usually diagnosed during a neurological exam with the doctor asking about the person’s symptoms.

It can be helpful to keep a symptom diary and share it with the doctor. The diary may include details such as when symptoms occur, how long they last, and the circumstances surrounding episodes.

Patients may be asked to complete specific clinical questionnaires about their symptoms, including the ability to control their laughter and crying.

PBA treatment

Treatment can involve PBA medications, including the combo dextromethorphan and quinidine, and antidepressants such as selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants.

Nuedexta is an approved oral therapy by the U.S. Food and Drug Administration  for the treatment of PBA; it is made of a combination dose of 20 mg of dextromethorphan hydrobromide and 10 mg of quinidine sulfate. Nuedexta has been shown to significantly reduce PBA symptoms and episodes.

SSRIs work to increase levels of the chemical messenger serotonin in the brain. Available SSRIs include:

• Celexa (citalopram)
• Lexapro (escitalopram)
• Zoloft (sertraline)
• fluoxetine (sold as Prozac, Sarafem, Rapiflux, Selfemra)
• paroxetine (sold as Paxil, Pexeva, Brisdelle).

Tricyclic antidepressants also cause changes in brain chemistry and improve communication in brain nerve cell circuitries known to regulate mood. Available tricyclic antidepressants include:

• amitriptyline (sold as Elavil, Endep, Vanatrip)
• Asendin (amoxapine)
• Norpramin (desipramine)
• doxepin
• Tofranil (imipramine)
• nortriptyline (Pamelor, Aventyl HCl)
• Vivactil (protriptyline)
• Surmontil (trimipramine).

An occupational therapist can help people learn to self-manage symptoms of PBA. Family members can be educated about PBA as well, which can lead to improved communication and help the person with PBA feel less isolated and more understood.

Some coping strategies can include distraction or changing body position to redirect the symptoms. Relaxation techniques such as mindfulness and meditation can also help reduce symptoms.

ALS News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.