Phencyclidine Positivity on Urine Drug Screening in Patients Treated for Alcohol Withdrawal on a Dual-diagnosis Medically Assisted Withdrawal Unit.

OBJECTIVES: Little contemporary research has explored phencyclidine (PCP) use in people with alcohol use disorder. Therefore, we sought to determine the prevalence of PCP positivity on urine toxicology screening among patients admitted for alcohol withdrawal, identify correlates of PCP positivity, and investigate PCP positivity's relationship to length of stay (LOS) and risk of facility readmission. METHODS: This was a retrospective study of patients admitted to a dual-diagnosis medically assisted withdrawal unit for alcohol withdrawal from 2014 to 2019. Univariate tests and logistic regression were used to investigate potential correlates of PCP positivity on admission toxicology screening (primary outcome). Multivariable linear regression models and survival analyses analyzing LOS and risk of readmission (secondary outcomes) were also developed. RESULTS: Ninety of 3731 patients (2.4%) screened positive for PCP. There were significant associations on univariate testing between PCP positivity and age, race, homeless status, and urine toxicology positivity for amphetamines, benzodiazepines, barbiturates, cocaine, tetrahydrocannabinol, and oxycodone. On multivariate logistic regression, only tetrahydrocannabinol, barbiturates, and cocaine positivity were associated with PCP positivity. Multivariate logistic regression and survival analysis found no statistically significant associations between PCP positivity and LOS or risk of readmission. CONCLUSIONS: This study provides rare analysis of contemporary data on PCP use among patients undergoing medically assisted alcohol withdrawal. Phencyclidine positivity was uncommon, but use appears considerably higher among this patient population than the general population. There was no significant association between PCP positivity and LOS or readmission risk.

Management of Phenibut Use Disorder and Withdrawal in a Geriatric Patient.

Phenibut is a misused substance which has shown an increase in use over the past decade. Marketed as a "dietary supplement," it is not approved in the United States for use and is not regulated by the Food and Drug Administration. The substance, however, is readily available for purchase through online markets. It has a similar drug profile as alcohol, gabapentin and benzodiazepines. Clinical effects of this drug include physiologic dependence, euphoria, anxiolysis, antispasticity, sedation, and possible nootropic properties. While there are emerging new cases of managing phenibut withdrawal, no cases currently feature phenibut addiction and withdrawal management in the geriatric population. Here we discuss such a case of phenibut addiction and withdrawal in a 68-year-old male who initially began misusing phenibut to alleviate anxiety and insomnia precipitated by worsening affective disorder, sedative, hypnotic, or anxiolytic use disorder, and alcohol use disorder.