Assessment of oral overlap with antipsychotic long-acting injectables initiated in an inpatient setting.

Introduction: Long-acting injectable (LAI) antipsychotics are a promising solution to combating issues related to nonadherence to oral antipsychotics. Oral overlap is utilized when an LAI is initiated to achieve therapeutic concentrations. The place in therapy in which additional overlap is warranted is often mistaken, and providers may prescribe additional overlap based on the presentation of the patient or misunderstanding of appropriate overlap.

Methods: This retrospective chart review assesses patients who were initiated on an LAI while admitted to the acute inpatient psychiatric unit from January 1, 2016, to December 31, 2019. The primary outcome assesses the appropriateness of oral overlap with LAIs. Secondary outcomes include adherence to oral overlap, discontinuation of an LAI within 4 months, and reason for discontinuation of LAI.

Results: A total of 62 patients were included: 40 (65%) had appropriate overlap, and 22 (35%) had inappropriate overlap. The most common LAI was paliperidone (n = 50, 81%). Patients were adherent to oral overlap in 67% (n = 6) of the appropriate overlap group and 85% (n = 17) of the inappropriate overlap group. Discontinuation of an LAI in 4 months occurred in 62.5% (n = 25) of the appropriate group and 40.9% (n = 9) of the inappropriate group. There were no significant differences in secondary outcomes when comparing adherence to oral overlap (p = .26), discontinuation of LAI within 4 months (p = .62), and reason for discontinuation (p = .69).

Discussion: This study identified that a majority of patients had appropriate prescribing of oral antipsychotic overlap.