Mechanisms supporting the social regulation of neural threat responding with marital partners: A test of the opioid hypothesis.

Positive social contact predicts better health, but the mechanisms for this association remain debated. One way to explore this link is through the social regulation of emotion, particularly anticipatory anxiety. Previous research finds less neural threat response during partner handholding than when people are alone or stranger handholding. Various mechanistic accounts have been forwarded, including the hypothesis that this effect is mediated by endogenous opioid activity. This experiment critically tested the opioid hypothesis in 60 married participants and their partners. The study used a naltrexone opioid blockade in a double-blind placebo control with functional magnetic resonance imaging to determine whether endogenous opioids were necessary for handholding effects. Regulatory effects of supportive handholding manifested in threat network regions during opioid blockade, but not with placebo. Despite a surprising lack of effect in the placebo group, the overall study findings provide initial evidence that endogenous opioids may not be necessary for the social regulation of neural threat responding.

Gabapentin Enacarbil Extended-Release for Alcohol Use Disorder: A Randomized, Double-Blind, Placebo-Controlled, Multisite Trial Assessing Efficacy and Safety.

BACKGROUND: Several single-site alcohol treatment clinical trials have demonstrated efficacy for immediate-release (IR) gabapentin in reducing drinking outcomes among individuals with alcohol dependence. The purpose of this study was to conduct a large, multisite clinical trial of gabapentin enacarbil extended-release (GE-XR) (HORIZANT® ), a gabapentin prodrug formulation, to determine its safety and efficacy in treating alcohol use disorder (AUD). METHODS: Men and women (n = 346) who met DSM-5 criteria for at least moderate AUD were recruited across 10 U.S. clinical sites. Participants received double-blind GE-XR (600 mg twice a day) or placebo and a computerized behavioral intervention (Take Control) for 6 months. Efficacy analyses were prespecified for the last 4 weeks of the treatment period. RESULTS: The GE-XR and placebo groups did not differ significantly on the primary outcome measure, percentage of subjects with no heavy drinking days (28.3 vs. 21.5, respectively, p = 0.157). Similarly, no clinical benefit was found for other drinking measures (percent subjects abstinent, percent days abstinent, percent heavy drinking days, drinks per week, drinks per drinking day), alcohol craving, alcohol-related consequences, sleep problems, smoking, and depression/anxiety symptoms. Common side-effects were fatigue, dizziness, and somnolence. A population pharmacokinetics analysis revealed that patients had lower gabapentin exposure levels compared with those in other studies using a similar dose but for other indications. CONCLUSIONS: Overall, GE-XR at 600 mg twice a day did not reduce alcohol consumption or craving in individuals with AUD. It is possible that, unlike the IR formulation of gabapentin, which showed efficacy in smaller Phase 2 trials at a higher dose, GE-XR is not effective in treating AUD, at least not at doses approved by the U.S. Food and Drug Administration for treating other medical conditions.

Smoked marijuana attenuates performance and mood disruptions during simulated night shift work.

Individuals who work nonstandard schedules, such as rotating or night shifts, are more susceptible to workplace injuries, performance decrements, and reduced productivity. This population is also almost twice as likely to use illicit drugs as individuals working a standard day shift. The purpose of this study was to examine the effects of smoked marijuana on performance, mood, and sleep during simulated shift work. Ten experienced marijuana smokers completed this 23-day, within-participant residential study. They smoked a single marijuana cigarette (0, 1.9, 3.56% Δ9-THC) one hour after waking for three consecutive days under two shift conditions: day shift and night shift. Shifts alternated three times during the study, and shift conditions were separated by an 'off' day. When participants smoked placebo cigarettes, psychomotor performance and subjective-effect ratings were altered during the night shift compared to the day shift: performance (e.g., vigilance) and a few subjective ratings were decreased (e.g., "Self-Confident"), whereas other ratings were increased (e.g., "Tired"). Objective and subjective measures of sleep were also disrupted, but to a lesser extent. Marijuana attenuated some performance, mood, and sleep disruptions: participants performed better on vigilance tasks, reported being less miserable and tired and sleep a greater number of minutes. Limited negative effects of marijuana were noted. These data demonstrate that abrupt shift changes produce performance, mood, and sleep decrements during night shift work and that smoked marijuana containing low to moderate Δ9-THC concentrations can offset some of these effects in frequent marijuana smokers.

Efficacy and safety of a sublingual buprenorphine/naloxone rapidly dissolving tablet for the treatment of adults with opioid dependence: A randomized trial.

This prospective, randomized, active-controlled, non-inferiority study evaluated the efficacy and safety of a sublingual buprenorphine/naloxone rapidly dissolving tablet (Zubsolv®; buprenorphine/naloxone rapidly dissolving tablet) versus generic buprenorphine for induction of opioid maintenance among dependent adults. The study, conducted at 13 sites from June 2013 to January 2014, included a 2-day blinded induction phase and a 27-day open-label stabilization/maintenance phase. During the blinded induction, patients received fixed doses of buprenorphine/naloxone rapidly dissolving tablets or generic buprenorphine. During open-label stabilization/early maintenance, all patients received buprenorphine/naloxone rapidly dissolving tablets. The primary efficacy assessment was treatment retention at day 3; buprenorphine/naloxone rapidly dissolving tablets were considered non-inferior to generic buprenorphine if the lower limit of the 95% confidence interval for the difference between the treatments was ≥-10% in patients retained on day 3. Secondary assessments included opioid withdrawal symptoms and cravings as measured using the Clinical Opiate Withdrawal Scale, the Subjective Opiate Withdrawal Scale, and the opioid cravings visual analogue scale. Safety was also assessed. A total of 313 patients were randomly assigned to induction with generic buprenorphine or buprenorphine/naloxone rapidly dissolving tablets. The mean age was 38.4 years, and the mean duration of opioid dependence was 12.4 years. For the primary efficacy assessment, 235 of 256 patients (91.8%) were retained at day 3 and continued to the maintenance phase. The lower limit of the 95% confidence interval was -13.7; thus, buprenorphine/naloxone rapidly dissolving tablets did not demonstrate non-inferiority to generic buprenorphine, and significantly more patients who received induction with generic buprenorphine (122/128 [95.3%]) were retained at day 3 compared with those who received induction with buprenorphine/naloxone rapidly dissolving tablets (113/128 [88.3%]; 95% confidence interval: -13.7, -0.4; p = 0.040). The rates of clinical response, as measured by the Clinical Opiate Withdrawal Scale, the Subjective Opiate Withdrawal Scale, and the visual analogue scale, were comparable among patients regardless of the induction medication. Treatment with buprenorphine/naloxone rapidly dissolving tablets was generally safe and reduced the severity of withdrawal symptoms and cravings.

Efficacy of Buprenorphine/Naloxone Rapidly Dissolving Sublingual Tablets (BNX-RDT) After Switching From BNX Sublingual Film.

OBJECTIVES: The aim of the study was to evaluate treatment retention, efficacy, and preference ratings among opioid-dependent patients transitioning between a buprenorphine/naloxone rapidly dissolving sublingual tablet formulation (BNX-RDT) and BNX film. METHODS: After a 2-day, blinded, fixed-dose induction with BNX-RDT (5.7/1.4 mg and 5.7/1.4 or 11.4/2.8 mg, respectively) or buprenorphine (8 mg and 8 or 16 mg, respectively), patients received open-label titrated doses of BNX-RDT or BNX film (generic buprenorphine induction group) during days 3 to 14. On day 15, patients switched treatment (using a conversion ratio of 5.7-8 mg) and continued switched treatment through day 22. Assessments included treatment retention, opioid withdrawal (Clinical and Subjective Opiate Withdrawal scales), opioid cravings (0-100 visual analog scale [VAS]), and preference ratings. RESULTS: Of the 287 patients who switched from BNX-RDT to BNX film and 279 patients who switched from BNX film to BNX-RDT at day 15, 8.7% and 6.1% withdrew, respectively. Reductions in opioid withdrawal and cravings were similar with both formulations through day 15; after switching treatment, reductions were maintained through day 22 in both groups. Preference ratings at day 22 (patients had received both formulations) favored BNX-RDT for taste, mouthfeel, ease of administration, and overall preference (all P < 0.0001). CONCLUSIONS: In both patient groups who switched treatment at day 15, more than 90% were retained in treatment, and reductions in opioid withdrawal and cravings were sustained. A significant majority of patients preferred BNX-RDT over BNX film, the clinical impact of which requires further study.

Effects of a higher-bioavailability buprenorphine/naloxone sublingual tablet versus buprenorphine/naloxone film for the treatment of opioid dependence during induction and stabilization: a multicenter, randomized trial.

PURPOSE: Sublingual buprenorphine and combination buprenorphine/naloxone (BNX) are effective options for the treatment of opioid dependence. A BNX sublingual tablet approved by the US Food and Drug Administration for the induction and maintenance treatment of opioid-dependence in adults was developed as a higher-bioavailability formulation, allowing for a 30% lesser dose of buprenorphine with bioequivalent systemic exposure compared with another BNX sublingual tablet formulation. No data were previously available comparing the higher-bioavailability BNX sublingual tablet to generic buprenorphine or BNX sublingual film; we therefore evaluated treatment retention during induction and stabilization with the higher-bioavailability BNX sublingual tablet versus generic buprenorphine or BNX sublingual film. METHODS: This multicenter, prospective, randomized, parallel-group noninferiority trial was conducted at 43 centers in the United States. Eligible patients were adults aged 18 to 65 years who met the criteria for opioid dependence and had at least mild withdrawal symptoms. On days 1 and 2, patients received blinded, fixed-dose induction with the higher-bioavailability BNX sublingual tablet or generic buprenorphine. On days 3 to 14, patients induced with BNX received open-label, titrated doses of the BNX tablet for stabilization; patients induced with buprenorphine received sublingual BNX film. Co-primary end points were treatment retention on days 3 and 15; noninferiority was concluded if the lower limit of the 95% CI of the between-group difference in treatment retention was ≥-10%. Tolerability was assessed throughout the study period. FINDINGS: A total of 758 opioid-dependent patients were included in the study (BNX sublingual tablet, 383 patients; generic buprenorphine, 375). Day-3 retention rates were 93.9% (309/329) and 92.6% (302/326) with the BNX tablet and buprenorphine, respectively (between-group difference 95% CI, -2.6 to 5.1). Day-15 retention rates were 83.0% (273/329) and 82.5% (269/326) with the BNX tablet and BNX film, respectively (between-group difference 95% CI, -5.3 to 6.3). No unexpected tolerability issues were identified; the safety profile of the BNX sublingual tablet was similar to those of generic buprenorphine and BNX film. IMPLICATIONS: Based on the findings from this study in patients with opioid dependence, the higher-bioavailability BNX sublingual tablet formulation was noninferior to both generic buprenorphine (induction) and BNX film (stabilization). These findings suggest that BNX sublingual tablets are an efficacious and well-tolerated option for induction and early stabilization treatment of opioid dependence. ClinicalTrials.gov identifier: NCT01908842.

Designer drugs 2015: assessment and management.

Recent designer drugs, also known as "legal highs," include substituted cathinones (e.g., mephedrone, methylone, and methylenedioxypyrovalerone, often referred to as "bath salts"); synthetic cannabinoids (SCs; e.g., Spice); and synthetic hallucinogens (25I-NBOMe, or N-bomb). Compound availability has evolved rapidly to evade legal regulation and detection by routine drug testing. Young adults are the primary users, but trends are changing rapidly; use has become popular among members of the military. Acute toxicity is common and often manifests with a constellation of psychiatric and medical effects, which may be severe (e.g., anxiety, agitation, psychosis, and tachycardia), and multiple deaths have been reported with each of these types of designer drugs. Clinicians should keep designer drugs in mind when evaluating substance use in young adults or in anyone presenting with acute neuropsychiatric complaints. Treatment of acute intoxication involves supportive care targeting manifesting signs and symptoms. Long-term treatment of designer drug use disorder can be challenging and is complicated by a lack of evidence to guide treatment.

Recognizing Potential Buprenorphine Medication Misuse: Product Packaging Does Not Degrade With Laundering.

BACKGROUND: Expanded office-based buprenorphine opioid dependence treatment is associated with medication misuse and diversion consequences. Recurrent early refill requests may indicate misuse or diversion, although further research is needed on how to effectively recognize and address the issue in clinical practice. In the current study, patient report of damaged medication from laundering prompted evaluation of laundering on degradation of buprenorphine-containing product packages and contents. METHODS: Four buprenorphine product packaging approaches were assessed: 3 buprenorphine/naloxone placebo demonstration products (Suboxone and Bunavail film in foil wrappers and Zubsolv tablet in a blister pack) and Rexam-manufactured Screw-Loc closure pill container filled with a chewable aspirin as a surrogate for generic buprenorphine and buprenorphine/naloxone products. Two experimental laundering conditions, wash machine alone (W) and washer/dryer (W+D), were compared with unlaundered control (C) condition. Standard laundering settings were based on patient presentation. Products from the 2 experimental conditions and the control condition were labeled A, B, or C with counterbalanced assignment prior to visual examination of packaging and contents by the investigator who was blinded to condition. RESULTS: Packaging and contents remained intact for all products across experimental conditions, with only minor cosmetic effects compared with control. The W+D Suboxone film had 1-2 mm curling of the wrapper corners. Zubsolv blister packs had slight paper label fading (W+D > W). Bunavail W+D foil had an indentation outlining the inner film. The W+D bottle tablet had a ˜1 mm nick on one edge. No other differences were noted. After implementing more structured treatment and reviewing the results with the patient, he endorsed fabricating the laundering story to get additional medication. CONCLUSIONS: Laundering is an unlikely cause of damaged buprenorphine-containing medication packaged in foil wrappers (Suboxone, Bunavail), blister pack (Zubsolv), or prescription pill bottle (generic buprenorphine or buprenorphine/naloxone products). Patient reports of such may indicate medication misuse or diversion.

A survey of synthetic cannabinoid consumption by current cannabis users.

BACKGROUND: Despite growing concern about the increased rates of synthetic cannabinoid (SC) use and their effects, only limited data are available that addresses these issues. This study assessed the extent of SC product use and reported effects among a cohort of adult marijuana and tobacco users. METHODS: A brief telephone interview was conducted with individuals who had given permission to be contacted for future research while screening for a cannabis/nicotine dependence medication development study (NCT01204723). RESULTS: Respondents (N = 42; 88% participation rate) were primarily young adults, male, racially diverse, and high school graduates. Nearly all currently smoked tobacco and cannabis, with 86% smoking cannabis on 5 or more days per week. Nearly all (91%) were familiar with SC products, half (50%) reported smoking SC products previously, and a substantial minority (24%) reported current use (i.e., past month). Despite a federal ban on 5 common SCs, which went into effect on March 1, 2011, a number of respondents reported continued SC product use. Common reasons reported for use included, but were not limited to, seeking a new "high" similar to that produced by marijuana and avoiding drug use detection via a positive urine screen. The primary side effects were trouble thinking clearly, headache, dry mouth, and anxiety. No significant differences were found between synthetic cannabinoid product users (ever or current) and nonusers by demographics or other characteristics. CONCLUSIONS: Among current marijuana and tobacco users, SC product consumption was common and persisted despite a federal ban. The primary reasons for the use of SC-containing products seem to be to evade drug detection and to experience a marijuana-like high.

Intranasal substituted cathinone "bath salts" psychosis potentially exacerbated by diphenhydramine.

In this report, we describe a case of intranasal "bath salts"-associated psychosis. Symptoms developed during a 3-week binge and were potentially exacerbated by oral diphenhydramine taken for insomnia. The clinical case conference includes expert discussion from 3 disciplines: emergency medicine toxicology, behavioral pharmacology, and addiction medicine. It is hoped that the discussion will provide insight into the clinical aspects and challenges of addressing acute substituted cathinone toxicity, including acute psychosis, a major adverse effect of bath salts consumption.

Substituted cathinone products: a new trend in "bath salts" and other designer stimulant drug use.

There is a growing concern about the availability of a new generation of "designer drug" stimulants that are marketed as "bath salts" and other household products. The products are not true bath salts and contain substituted cathinone stimulant substances, such as methylenedioxypyrovalerone (MDPV) and mephedrone. Calls to the American Association of Poison Control Centers regarding "bath salts" consumption began in 2010 and have continued since that time. Few reports of systematic epidemiologic surveillance or definitive clinical effects of toxicity specifically associated with "bath salts" consumption have been reported in the medical literature. The current narrative review describes the growing trend of designer substituted cathinone use, pharmacology, clinical effects, and recent regulatory changes. It is hoped that a greater understanding of the clinical effects and use patterns will help inform policy and practice.

Topiramate's effects on cocaine-induced subjective mood, craving and preference for money over drug taking.

Topiramate, presumably through antagonism of excitatory glutaminergic pathways and facilitation of inhibitory gamma-aminobutyric acid neurons in the cortico-mesolimbic system, might reduce cocaine's abuse liability. We tested whether topiramate (100 mg twice daily) would reduce the euphoria, subjective mood, craving and preference for cocaine over money induced by low and high doses (0.325 and 0.65 mg/kg i.v., respectively) of experimentally administered cocaine in 24 male and female, cocaine-dependent, non-treatment-seeking research volunteers in a university in-patient laboratory. We utilized a randomized, double-blind, placebo-controlled, within-subject, Latin-square cross-over design in which three experimental challenge doses of low-dose cocaine, high-dose cocaine and placebo were administered in counterbalanced order after 5 days of topiramate or matching placebo pre-treatments separated by a 1-week washout period (2006-2009). After placebo pre-treatments, cocaine produced dose-related increases in euphoria, stimulant effects, craving for more cocaine and monetary value of cocaine in a behavioral preference test of cocaine versus money choice. Topiramate pre-treatment reduced the cocaine-related craving and monetary value of high-dose cocaine while increasing the monetary value, euphoria and stimulant effects of low-dose cocaine. Validated and standardized human experimental methods evaluating the potential for topiramate to alter cocaine's abuse liability suggest that topiramate may reduce the reinforcing effects and craving induced by higher cocaine doses. Low-dose cocaine might appear to have some enhancement of its stimulant properties in the presence of topiramate's prominent sedative effects.

"Spice" and "K2" herbal highs: a case series and systematic review of the clinical effects and biopsychosocial implications of synthetic cannabinoid use in humans.

Cannabis, the most commonly used illicit substance, exerts its primary psychoactive effect via delta-9 tetrahydrocannabinol (Δ(9) -THC) agonism of cannabinoid receptor type 1 (CB1). Some users develop a cannabis use disorder and physical dependence manifested by withdrawal symptoms during abstinence. Hence, there is growing public health concern about increasing use of a new generation of synthetic cannabinoid (SC) agonists (eg, JWH-018, CP 47,497) marketed as natural herbal incense mixtures under brand names such as "Spice" and "K2." Anecdotal reports suggest overlapping effects with marijuana when the mixtures are smoked, however, systematic evaluation of SC-related psychoactive properties and adverse effects is lacking. We conducted a systematic review of published reports on SC clinical effects in humans. Most highlight potential toxicity such as acute anxiety and psychosis. In addition, we carefully document three cases in which experienced marijuana users meeting criteria for cannabis dependence with physiologic dependence smoked SC products regularly. The SC mixture effects were reportedly similar to marijuana and well tolerated. The individuals all reported that SC product use effectively alleviated cannabis withdrawal. Biopsychosocial factors associated with SC initiation and usage by the cases help to shed light on psychopharmacologic, clinical, and public health aspects of SC product consumption.

A direct comparison of the behavioral and physiological effects of methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA) in humans.

RATIONALE: Despite their chemical similarities, methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA) produce differing neurochemical and behavioral responses in animals. In humans, individual studies of methamphetamine and MDMA indicate that the drugs engender overlapping and divergent effects; there are only limited data comparing the two drugs in the same individuals. OBJECTIVES: This study examined the effects of methamphetamine and MDMA using a within-subject design. METHODS: Eleven adult volunteers completed this 13-day residential laboratory study, which consisted of four 3-day blocks of sessions. On the first day of each block, participants received oral methamphetamine (20, 40 mg), MDMA (100 mg), or placebo. Drug plasma concentrations, cardiovascular, subjective, and cognitive/psychomotor performance effects were assessed before drug administration and after. Food intake and sleep were also assessed. On subsequent days of each block, placebo was administered and residual effects were assessed. RESULTS: Acutely, both drugs increased cardiovascular measures and "positive" subjective effects and decreased food intake. In addition, when asked to identify each drug, participants had difficulty distinguishing between the amphetamines. The drugs also produced divergent effects: methamphetamine improved performance and disrupted sleep, while MDMA increased "negative" subjective-effect ratings. Few residual drug effects were noted for either drug. CONCLUSIONS: It is possible that the differences observed could explain the differential public perception and abuse potential associated with these amphetamines. Alternatively, the route of administration by which the drugs are used recreationally might account for the many of the effects attributed to these drugs (i.e., MDMA is primarily used orally, whereas methamphetamine is used by routes associated with higher abuse potential).

Acute and residual interactive effects of repeated administrations of oral methamphetamine and alcohol in humans.

Although methamphetamine and alcohol are commonly used together in a binge-like pattern, there is a dearth of empirical data investigating the repeated effects of this drug combination. The current study examined acute and residual mood, performance, and physiological effects of methamphetamine alone, alcohol alone, and the combination. Nine adult male volunteers completed this 20-day within-participant, residential laboratory study. During four 5-day blocks of sessions, participants were administered oral methamphetamine (0, 10 mg) combined with alcohol (0, 0.375, 0.75 g/kg) three times (day 2: AM, day 2: PM, and day 3: PM). Breath alcohol concentrations, cardiovascular, subjective, and cognitive/psychomotor performance effects were assessed before drug administration and repeatedly thereafter. Subjective and objective sleep measures were also assessed; residual effects were assessed on days 3-5 of each block. Following the first drug administration, the methamphetamine-alcohol combination produced greater elevations of heart rate and ratings of "good drug effect" compared to either drug alone. Methamphetamine attenuated alcohol-related performance decrements and feelings of intoxication, whereas alcohol attenuated methamphetamine-related sleep disruptions. By the third administration, many of these effects were significantly diminished, suggesting that participants developed tolerance. Few residual effects were observed. These data show that methamphetamine combined with alcohol produced a profile of effects that was different from the effects of either drug alone. The largely positive effects of the drug combination (i.e., greater euphoria, and fewer performance and sleep disruptions) might explain why these drugs are often used in combination.

Comparison of intranasal methamphetamine and d-amphetamine self-administration by humans.

AIMS: There are no studies directly comparing self-administration of methamphetamine and d-amphetamine by humans. This study compared intranasal methamphetamine- and d-amphetamine self-administration and characterized the mood, performance and physiological effects produced by the drugs. DESIGN: A randomized, double-blind, placebo-controlled, cross-over study. SETTING: An out-patient research unit at the New York State Psychiatric Institute. PARTICIPANTS: Male recreational methamphetamine users (n = 13). MEASUREMENTS: Five 2-day blocks of sessions were conducted. On the first day of each block, participants 'sampled' a single methamphetamine or d-amphetamine dose (0, 12, 50 mg/70 kg) and a monetary reinforcer ($5 or $20). Amphetamine plasma levels, cardiovascular, mood, and psychomotor performance effects were assessed before drug administration and repeatedly thereafter. On the second day of each block, participants chose between the sampled reinforcers (drug or money). FINDINGS: There were no significant differences between the drugs on the majority of measures. Under the $5 condition, both amphetamines increased self-administration dose-dependently, with 41% drug choices overall. Under the $20 condition, only 17% drug options were selected. Both drugs increased cardiovascular activity and 'positive' mood, although methamphetamine produced more prominent effects on some measures (e.g. heart rate and ratings of 'high'). CONCLUSIONS: Methamphetamine and d-amphetamines appear to produce a similar dose-related profile of effects in humans, which supports their equivalence for abuse potential.

Improving temporal efficiency of outpatient buprenorphine induction.

Buprenorphine induction poses a barrier for physician adoption of office-based opioid dependence treatment. We conducted a retrospective chart review of the first 41 patients inducted at a newly established outpatient treatment program to examine the induction process and determine strategies associated with greater induction efficiency. Timed withdrawal scales, medication log, and notes enabled reconstruction of the initial day of buprenorphine treatment. To assess change with experience, consecutive patients were divided into three chronological groups for analyses (Phases 1-3). The time required for induction was substantial in Phase 1 (mean 5.5 hours), but temporal efficiency improved to a mean 1.5 hours spent at the program by Phase 3 (p < .001). Phase 2-3 patients arrived to the program after significantly longer opioid abstinence and were in greater withdrawal, with mean Clinical Opioid Withdrawal Scale scores of 6, 10, and 10 for Phases 1-3, respectively (p < .01). Patients in the later phases had less time delay to medication initiation, 5 minutes in Phase 3 compared to 133 minutes in Phase 1 (p < .001). The mean 7-mg buprenorphine dose administered in the office did not differ between groups, but occurred over a smaller time interval for later phases indicating more rapid titration. Patients in the later phases had more rapid withdrawal relief after buprenorphine initiation and were more likely to have used preinduction ancillary withdrawal medication. The study sheds light on the induction barrier and provides practical procedural information to inform clinical guidelines and hopefully mitigate procedural aspects of the induction barrier.