Outcomes associated with once-daily versus multiple-daily dosing of buprenorphine/naloxone for opioid use disorder.

BACKGROUND AND OBJECTIVES: Clinical studies examining once-daily versus multiple-daily dosing of buprenorphine/naloxone in patients with opioid use disorder (OUD) in the absence of comorbid pain are lacking. METHODS: This retrospective chart review aimed to compare 100 patients prescribed single-daily buprenorphine/naloxone (n = 50) to those prescribed multiple-daily buprenorphine/naloxone (n = 50) to elucidate the impact that dosing frequency has on negative urine drug screens (UDS) and the number of relapses in OUD. RESULTS: The once-daily cohort produced 84% negative UDSs compared with 74% in the multiple-daily cohort which was statistically significant (p = .034). There were a total of 43 relapses reported in the once-daily cohort, compared with 141 relapses in the multiple-daily cohort (p < .001). The average number of relapses per patient in the single-daily cohort was 0.68 compared with the multiple-daily cohort average of 2.16 (p < .001). In the once-daily cohort, 14% of patients experienced at least one relapse throughout the study, compared with 31% in the multiple-daily cohort (p < .002). There were no significant differences between time to relapse, adherence to treatment, or treatment retention. Statistically significantly more patients in the multiple-daily cohort were using methamphetamines (p = .005); there were no significant differences between groups with the use of any other illicit or non-prescribed substances. DISCUSSION AND CONCLUSIONS: Once-daily dosing was associated with more negative UDSs and fewer opioid relapses compared with multiple-daily dosing. SCIENTIFIC SIGNIFICANCE: This was the first study to evaluate buprenorphine/naloxone dosing frequency for opioid use disorder, in the absence of chronic pain. Additional studies evaluating optimal dosing schedules for relapse prevention are warranted.

Alcohol withdrawal-related outcomes associated with gabapentin use in an inpatient psychiatric facility.

INTRODUCTION: Limited evidence exists evaluating the impact of gabapentin in conjunction with benzodiazepines for the management of alcohol withdrawal. A review of outcomes associated with combination gabapentin and benzodiazepine therapy may illuminate new therapeutic uses in clinical practice. METHODS: This retrospective study evaluated the impact of gabapentin on as-needed use of benzodiazepines in inpatients being treated for acute alcohol withdrawal. The treatment cohort consisted of patients prescribed gabapentin while on a symptom-triggered alcohol withdrawal protocol. The control cohort consisted of patients on symptom-triggered alcohol withdrawal protocol without concurrent gabapentin use. Secondary objectives included length of hospital stay, duration on alcohol withdrawal protocol, frequency of complicated withdrawal, and use of additionally prescribed as-needed or scheduled benzodiazepines. RESULTS: The gabapentin cohort was on the alcohol withdrawal protocol for a similar duration, compared with the control cohort (median of 4 [interquartile range: 2,6] days vs 3 [2,4] days, P = .09, respectively). Similarly, the gabapentin cohort required a median of 1 [1,2] benzodiazepine dose for alcohol withdrawal symptoms compared with a median of 1 [1,2] dose in the control cohort, P = .89. No significant difference was found between cohorts for as-needed and scheduled benzodiazepine use. Length of stay in hospital was similar between groups. DISCUSSION: These results suggest that gabapentin use, in conjunction with benzodiazepines, impacts neither the time on alcohol withdrawal protocol or the number of benzodiazepine doses required for withdrawal. Larger, prospective studies are needed to detect if gabapentin alters benzodiazepine usage and to better elucidate gabapentin's role in acute alcohol withdrawal.

Anti-NMDA receptor encephalitis: An emerging differential diagnosis in the psychiatric community.

Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is a new diagnosis, as recent as 2007, that develops as a result of autoantibodies to the NMDA receptor. The clinical manifestations of the disorder include complex psychiatric symptoms, seizures, movement disorders, cognitive dysfunction, and autonomic instability. Tumor resection, if present, and immunotherapy are the mainstays of therapy. Treatment should be initiated early and aggressively as it has been associated with better patient outcomes. A significant proportion of patients with anti-NMDA receptor encephalitis initially seek the help of a psychiatrist, highlighting the importance of its recognition within the mental health community. In an effort to promote disease awareness, this article will review a patient case and the pathophysiology, clinical presentation, diagnosis, and management of anti-NMDA receptor encephalitis.

Lithium dosing equations: are they accurate?

BACKGROUND: Several equations are used to predict lithium doses necessary to attain therapeutic serum concentrations. A number of studies have evaluated these equations; however, few equations were compared simultaneously. OBJECTIVE: To assess the accuracy and precision of published dosing equations in predicting daily lithium doses and to evaluate if pertinent laboratory tests were performed prior to initiation. METHODS: A retrospective analysis was performed of patients who received lithium at the Medical University of South Carolina Institute of Psychiatry between July 2010 and July 2012. Using dosing equations, expected lithium doses were calculated based on corresponding serum concentrations identified in patient charts. Expected doses were then compared with actual lithium doses. The primary end point was to assess the accuracy and precision of dosing equations using mean differences in daily lithium doses and standard deviations. Secondary end points included presence of pertinent laboratory tests and use of concomitant interacting drugs . RESULTS: Of 155 patients identified, 59 were eligible for analysis. Equations developed by Abou-Auda et al and Pepin et al did not predict doses that were significantly different from actual doses. Conversely, equations by Jermain et al, Terao et al, and Zetinet al did predict statistically different doses. CONCLUSIONS: Abou-Auda et al developed a predictive lithium dosing equation that was more accurate than equations developed by Jermain et al, Terao et al, and Zetin et al and more precise than the Pepin et al equation. Further study evaluating the influence of equations on clinical outcomes is warranted.