OBJECTIVES: Pseudobulbar affect (PBA) is a neurological condition characterized by uncontrolled outbursts of laughter or crying. It occurs secondary to brain injury or neurologic disease.  PBA is often confused with other mental health (MH) conditions, and is challenging to identify retrospectively with claims data because an ICD-9-CM diagnosis code was not designated until late 2011. PBA is often treated with antidepressants, anticonvulsants, antipsychotics, or anxiolytics. Estimated prevalence of PBA secondary to stroke is 7% to 50%. Our study objective was to identify PBA in a population of post-stroke patients. METHODS: Commercial and Medicare Advantage members with incident stroke from January 1, 2007 to February 28, 2010 were identified with retrospective claims data from a large US health plan. Patients were continuously enrolled for 12 months pre- and post-stroke. Those with: stroke care, MH conditions (depression, bipolar, generalized anxiety or personality disorders), antidepressants, or diagnoses of emotional lability (ICD-9 799.24, 310.8x) pre-stroke were excluded. Post-stroke PBA was identified with: ICD-9 codes for emotional lability; ≥1 MH-related ambulatory visit; or ≥1 claim for a selective serotonin reuptake inhibitor (SSRI) or serotonin and norepinephrine reuptake inhibitor (SNRI) plus ≥1 claim for anticonvulsant, antipsychotic, or anxiolytic within 6 months post-stroke. Sensitivity of the criteria was tested by requiring more medication claims or adding MH-related hospitalization. RESULTS: The study population comprised 9408 post-stroke patients. The PBA criteria identified 605 (10.3%) of commercial and 253 (7.1%) of Medicare Advantage subjects. Less than 1% had diagnoses indicating emotional lability. Stricter medication criteria reduced the PBA cohort <2 percentage points, indicating most patients had multiple SSRI, SNRI, and other medication fills. MH-related hospitalizations increased the PBA cohort <1 percentage point. Overall, 8.6-11.1% of commercial and 6.6-7.9% of Medicare Advantage patients had potential PBA, depending on criteria. CONCLUSIONS: The criteria identified a stable potential PBA cohort within the range of estimated PBA prevalence.