The causes and treatment of pseudobulbar affect in ischemic stroke.

Pseudobulbar affect (PBA) is a disorder of emotional regulation characterized by uncontrollable outbursts of laughing and/or crying that are disproportionate to the emotions being experienced. The pathophysiology of PBA is currently unknown, although the disorder is thought to occur exclusively in the setting of neurologic disease, including stroke. The most influential theory on PBA posits that emotional outbursts are being generated in the brainstem autonomously due to loss of regulatory control by the frontal lobes. Although rarely life threatening, PBA can have significant impact on patients' quality of life and thus merits treatment. Although currently there are no treatments approved by the Food and Drug Administration (FDA) for PBA, tricyclic antidepressants and selective serotonin reuptake inhibitors are commonly used. Both these treatments are inexpensive and relatively low risk, although the quality of the available data on their efficacy is not optimal. Recently, a new agent containing dextromethorphan and quinidine (DM/Q) demonstrated efficacy in treating PBA in two large clinical trials--one in patients with multiple sclerosis and the other in patients with amyotrophic lateral sclerosis. Further studies are being conducted. If DM/Q is approved for PBA treatment, it will be the first agent approved by the FDA for this purpose. The choice of whether to use DM/Q in this setting will likely depend on individual patient factors. Currently, the antidepressants are probably the most attractive pharmacologic options for treating PBA. Although nonpharmacologic therapies have not been studied systematically, they should be explored in cognitively intact patients.