Category: Federal Forum Posters
Purpose: Prescribing two or more antipsychotics is common in the treatment of schizophrenia and psychotic disorders. Potential concerns about combining antipsychotics include: increase in adverse effects, drug interactions and non-adherence. Based on Joint Commission's performance measures and clinical practice guidelines, antipsychotic polypharmacy should not be utilized until a veteran has failed monotherapy and clozapine. Clozapine is a treatment of choice for veterans whose symptoms have not improved with other antipsychotic treatments. The purpose of this project was to observe the prescribing practices of antipsychotic polypharmacy at VACCHCS and to evaluate whether these veterans could be eligible for clozapine.
Methods: This single-center, cross-sectional review was conducted at VACCHCS. Using the electronic health record system, all veteran prescriptions for two or more antipsychotic medications were selected from July 2017 to June 2018. Inpatient antipsychotic drug prescriptions were not considered. Veterans were included if they had schizophrenia or psychotic disorder(s), and had filled at least two antipsychotic drug prescriptions for the same medical condition at the same time. The antipsychotic drugs considered include oral formulation and long acting injectable for first generation antipsychotics (FGA) and second generation antipsychotics (SGA). Antipsychotic medications prescribed for sleep, as needed (PRN), or tapering regimen were excluded from this review. The primary outcome was to observe the number of veterans on antipsychotic polypharmacy whose medications were prescribed appropriately and the number of veterans whose medication were prescribed inappropriately and therefore were potentially eligible for clozapine. The 2014 National Institute of Health and Clinical Excellence (NICE) guideline was used to observe the appropriateness of these prescriptions and to evaluate the eligibility for clozapine.
Results: A total of 59 veterans were prescribed at least two antipsychotic medications at VACCHCS from July 2017 to June 2018. Of the 59 charts reviewed, 54 percent (n=32) met the inclusion criteria and 46 percent (n=27) were excluded. The primary reasons for exclusion were: diagnosis other than schizophrenia or psychotic disorders (34 percent, n=20), and antipsychotic medications prescribed for sleep, PRN, or tapering regimen (12 percent, n=7). Of 32 veterans who met the inclusion criteria, 16 percent (n=5) were prescribed appropriately and 84 percent (n=27) were prescribed inappropriately. Of the 27 veterans who were prescribed inappropriately, 44 percent (n=12) had only trialed one SGA prior to starting antipsychotic polypharmacy, 56 percent (n=15) had trialed at least two or more antipsychotics. As a result, 15 veterans were potentially eligible for clozapine.
Conclusion: By observing the prescribing practice of antipsychotic polypharmacy, the appropriateness of these prescriptions can be determined and therefore reduce the risks of adverse effects and drug-drug interactions. Results from this review imply that clozapine is underutilized. There are many reasons why psychiatrists are reluctant to start treatment with clozapine, those including side effects, ongoing ANC monitoring, time and transportation to the clinic. Additional reviews are needed to determine the necessity of clozapine for veterans. Furthermore, education and changes in practices may be needed to reduce the number of antipsychotic polypharmacy prescriptions.
Joann Maithy Phan– PGY1 Pharmacy Resident, Veterans Affairs Central California Health Care System (VACCHCS), Sunnyvale, CA