Pseudobulbar Affect – A Disabling but Under-recognised Consequence of Neurological Disease and Brain Injury

Abstract

Pseudobulbar affect (PBA) is a condition associated with common neurological diseases or brain injury that manifests as uncontrollable and inappropriate outbursts of laughter or crying. PBA exacts a severe burden on the patient and care-givers in terms of reduced social functioning and often results in the patient’s isolation. The pathophysiology of PBA is incompletely understood, but symptoms are thought to result from damage to neural pathways associated with motor functioning and emotional processing. Data suggest that PBA is under-recognised by neurologists and psychiatrists and many cases go unrecognised or misdiagnosed. PBA has been successfully treated with psychoactive drugs, including antidepressants, but these do not have regulatory approval for use in this indication. A combination of dextromethorphan hydrobromide and quinidine sulphate (DM/Q) has demonstrated significant efficacy in reducing PBA symptoms and a favourable safety profile in a series of clinical trials and in regular clinical use. With the availability of an effective treatment for PBA symptoms, it becomes even more pressing to detect the condition so that patients can receive appropriate treatment.