Initiation of Antipsychotic Treatment for Amphetamine Induced Psychosis and Its Impact on Length of Stay

Introduction: A risk of amphetamine use is amphetamine-induced psychosis (AIP). Symptoms of AIP include hallucinations, delusions, and agitation. While AIP may resolve with abstinence from amphetamines, antipsychotics are commonly used despite not being FDA approved. The primary objective of this study was to compare length of stay (LOS) for patients with AIP treated with antipsychotics vs untreated. Secondary aims were to determine antipsychotic prescribed, proportion of patients utilizing as needed doses, time to initiation, and readmissions. Methods: A retrospective chart review conducted at an academic medical center identified adult participants who were diagnosed with AIP, admitted to inpatient psychiatry service, and had a urine drug screen (UDS) positive for amphetamines. Patients were excluded if they were already taking an antipsychotic, had active prescriptions for amphetamine salts, or were in the emergency department for more than 48 hours. Demographics were assessed with descriptive statistics. Length of stay was compared between treatment groups using Kruskal-Wallis. Secondary aims were assessed using chi-square, Mann-Whitney U, and Kruskal-Wallis. Results: Sixty-nine patients were included. Median LOS for patients treated with antipsychotics (n = 35) was longer than untreated patients (n = 34), (5 days vs 2.5 days, P = .001). Type of antipsychotic used and time to initiation of antipsychotic were not found to affect LOS. There was no difference in readmissions rates and positive UDS on readmission between groups. Conclusion: This study found patients with scheduled antipsychotics for AIP had a longer LOS than patients who did not receive scheduled antipsychotics. Future studies are needed to evaluate antipsychotic use in AIP.