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.

These data suggest that for experienced marijuana smokers with clinically significant muscle mass loss, both dronabinol (at acute doses at least four to eight times the current recommendation) and marijuana produce substantial and comparable increases in food intake without producing adverse effects.

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 five 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 non-users 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. (Support: DA027131)

Intranasal methamphetamine abuse has increased dramatically in the past decade, yet only one published study has investigated its acute effects under controlled laboratory conditions. Thus, the current study examined the effects of single-dose intranasal methamphetamine administration on a broad range of behavioral and physiological measures. Eleven nontreatment-seeking methamphetamine abusers (two females, nine males) completed this four-session, in-patient, within-participant, double-blind study. During each session, one of four intranasal methamphetamine doses (0, 12, 25, and 50 mg/70 kg) was administered and methamphetamine plasma concentrations, cardiovascular, subjective, and psychomotor/cognitive performance effects were assessed before drug administration and repeatedly thereafter. Following drug administration, methamphetamine plasma concentrations systematically increased for 4 h postdrug administration then declined. Methamphetamine dose dependently increased cardiovascular measures and 'positive' subjective effects, with peaks occurring approximately 5-15 min after drug administration, when plasma levels were still ascending. In addition, cognitive performance on less complicated tasks was improved by all active methamphetamine doses, whereas performance on more complicated tasks was improved only by the intermediate doses (12 and 25 mg). These results show that intranasal methamphetamine produced predictable effects on multiple behavioral and physiological measures before peak plasma levels were observed. Of interest is the dissociation between methamphetamine plasma concentrations with cardiovascular measures and positive subjective effects, which might have important implications for potential toxicity after repeated doses. INTRODUCTIONAlthough methamphetamine abuse has increased dramatically over the past decade, much of our knowledge about its acute effects in humans is anecdotal. The drug is frequently abused via the intranasal, i.v., and smoked routes (Domier et al, 2000; Community Epidemiology Work Group, 2005), but few studies have evaluated the acute effects of methamphetamine in humans using these routes of administration. The majority of studies conducted with humans have focused primarily on the cardiovascular and subjective effects produced by oral methamphetamine, a route of administration least often associated with abuse presumably due to its slow onset of effects. The onset of peak effects produced by oral methamphetamine does not occur until about 90 min after the administration (Hart et al, 2001a). By comparison, peak effects produced by intranasal, smoked, and i.v. methamphetamine occur within 15 min (Harris et al, 2003;Newton et al, 2005).Given that the rapidity of drug-related effects is a critical determinant of abuse liability (Hatsukami and Fischman, 1996), it is surprising that only a few studies have examined methamphetamine-related effects via routes of administration other than oral (eg Cook et al, 1993;Mendelson et al, 1995;Newton et al, 2006). Although inhalation by s...

Background Rates of relapse among cocaine-dependent patients are high, and new treatment approaches are needed. Clinical data demonstrate that a cocaine vaccine (TA-CD: Celtic Pharmaceutical) produces selective anti-cocaine antibodies, yet the impact of these antibodies on cocaine’s direct effects is unknown. The objective of this human laboratory study was to measure the relationship between antibody titers and the effects of smoked cocaine on ratings of intoxication, craving and cardiovascular effects. Methods Ten cocaine-dependent men not seeking drug treatment spent 2 nights per week for 13 weeks inpatient where the effects of cocaine (0, 25, 50 mg) were determined prior to vaccination and at weekly intervals thereafter. Two doses of TA-CD (82 µg, n=4; 360 µg, n=6) were administered at weeks 1, 3, 5 and 9. Results Peak plasma antibody levels, which were highly variable, significantly predicted cocaine’s effects. Those individuals in the upper half of antibody production had an immediate (within 4 minutes of cocaine smoking) and robust (55–81%) reduction in ratings of Good Drug Effect and Cocaine Quality, while those in the lower half showed only a nonsignificant attenuation (6–26%). Self-reported cocaine use while participants were outpatient tended to decrease as a function of antibody titer (p < 0.12). By contrast, higher antibody levels predicted significantly greater cocaine-induced tachycardia. Conclusions The TA-CD vaccine substantially decreased smoked cocaine’s intoxicating effects in those generating sufficient antibody. These data support further testing of cocaine immunotherapy as a treatment for cocaine dependence.

RATIONALE Previously, we reported that acute marijuana intoxication minimally affected complex cognitive performance of daily marijuana smokers. It is possible that the cognitive tests used were insensitive to marijuana-related cognitive effects. OBJECTIVES In the current study, electroencephalographic (EEG) signals were recorded as daily marijuana users performed additional tests of immediate working memory and delayed episodic memory, before and after smoking marijuana. METHODS Research volunteers (N=24), who reported smoking ~24 marijuana cigarettes/week, completed this study. Participants completed baseline computerized cognitive tasks, smoked a single marijuana cigarette (0%, 1.8%, or 3.9% Δ9-THC w/w), and completed additional cognitive tasks; sessions were separated by at least 72-hrs. Cardiovascular and subjective effects were also assessed throughout sessions. RESULTS Overall performance accuracy was not significantly altered by marijuana, although the drug increased response times during task performance and induced a response bias towards labeling “new” words as having been previously seen in the verbal episodic memory task. Marijuana reduced slow wave evoked potential amplitude in the episodic memory task and decreased P300 amplitude and EEG power in the alpha band in the spatial working memory task. Heart rate and “positive” subjective-effect ratings were increased in a Δ9-THC concentration-dependent manner. CONCLUSIONS Relative to previous findings with infrequent marijuana users, the frequent users in the current study exhibited similar neurophysiological effects but more subtle performance effects. These data emphasize the importance of taking into account the drug-use histories of research participants and examining multiple measures when investigating marijuana-related effects on cognitive functioning.

The importance of training physicians to effectively assess and manage substance use disorders has become increasingly recognized. Studies highlighting the effort to enhance curricula are described and common practices identified. Preferable curricula incorporate interactive teaching methods along with experiential and didactic components. Addiction specialists serve an important role in training programs designed for medical students and residents (ie, role models) and practicing physicians (ie, clinical support). Further integration of online training into current programs may expand and enhance training opportunities.

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).