What is the treatment for pseudobulbar affect (PBA)?

Treatment for Pseudobulbar Affect (PBA)

Dextromethorphan/quinidine is the FDA-approved first-line treatment for pseudobulbar affect, with strong evidence supporting its efficacy in reducing the frequency and severity of inappropriate emotional outbursts. 1

Understanding Pseudobulbar Affect

• PBA is characterized by inappropriate involuntary outbursts of laughing and/or crying that are disproportionate to the emotions being experienced, affecting 10-48% of stroke patients 1
• PBA occurs in the setting of neurological conditions including stroke, traumatic brain injury, ALS, MS, Alzheimer's disease, and Parkinson's disease 2
• The condition significantly impacts quality of life, causing social embarrassment and isolation 3

First-Line Treatment

• Dextromethorphan/quinidine (Nuedexta®) is FDA-approved specifically for PBA treatment 1, 2
• The recommended dosage is 20mg dextromethorphan/10mg quinidine twice daily 2
• The combination utilizes quinidine to inhibit metabolism of dextromethorphan, enabling therapeutic plasma concentrations 2
• Clinical trials have demonstrated significant reduction in PBA episode frequency and severity in patients with various neurological conditions 2, 3

Treatment Algorithm

1. Initial Assessment:

   • Confirm PBA diagnosis using validated tools such as the Pathological Laughing and Crying Scale or the Center for Neurological Study-Liability Scale 1
   • Distinguish PBA from depression or other mood disorders 1

2. First-Line Treatment:

   • Start dextromethorphan/quinidine 20mg/10mg twice daily 2
   • Monitor for response over 1-2 weeks 3

3. Alternative Options (if dextromethorphan/quinidine is contraindicated or unavailable):

   • Antidepressants, particularly SSRIs, have shown efficacy in small studies 4, 5
   • Tricyclic antidepressants may also be considered 5

Special Considerations

• Use dextromethorphan/quinidine with caution in adults over 70 years old due to potential increased risk of falls and drug-drug interactions 1
• For patients taking angiotensin-converting enzyme inhibitors or angiotensin receptor blockers with reduced kidney function, monitor for potential drug interactions 1
• Consider potential interactions with other medications that affect serotonin levels to avoid serotonin syndrome 4

Non-Pharmacological Management

• Cognitive and emotional therapy, psychotherapy, and support groups can be beneficial adjuncts to medication 1
• Patient and family education about PBA can help defuse potentially uncomfortable social situations 1
• Acknowledge the condition to reduce patient and caregiver distress 1

Monitoring and Follow-up

• Reassess patients within one month after initiating treatment to confirm symptom resolution 1
• Monitor for common side effects including dizziness, nausea, and headache 2
• Evaluate for continued need of medication as some patients may experience improvement over time 4

Common Pitfalls to Avoid

• Misdiagnosing PBA as depression or other psychiatric conditions, leading to inappropriate treatment 5
• Failing to recognize PBA in patients with neurological conditions, leaving the condition untreated 6
• Using vestibular suppressants like meclizine which do not address the underlying mechanism of PBA 1