Residual sleepiness after N(2)O sedation: a randomized control trial [ISRCTN88442975]

BACKGROUND: Nitrous oxide (N(2)O) provides sedation for procedures that result in constant low-intensity pain. How long do individuals remain sleepy after receiving N(2)O? We hypothesized that drug effects would be apparent for an hour or more. METHODS: This was a randomized, double blind controlled study. On three separate occasions, volunteers (N = 12) received 100% oxygen or 20% or 40% N(2)O for 30 min. Dependent measures included the multiple sleep latency test (MSLT), a Drug Effects/Liking questionnaire, visual analogue scales, and five psychomotor tests. Repeated measures analysis of variance was performed with drug and time as factors. RESULTS: During inhalation, drug effects were apparent based on the questionnaire, visual analogue scales, and psychomotor tests. Three hours after inhaling 100% oxygen or 20% N(2)O, subjects were sleepier than if they breathed 40% N(2)O. No other drug effects were apparent 1 hour after inhalation ceased. Patients did not demonstrate increased sleepiness after N(2)O inhalation. CONCLUSION: We found no evidence for increased sleepiness greater than 1 hour after N(2)O inhalation. Our study suggests that long-term effects of N(2)O are not significant

Post-puff respiration measures on smokers of different tar yield cigarettes

The purpose of this study was to determine the effect of different tar yield cigarette brands on the post-puff inhalation/exhalation depth and duration for established smokers of the brands. The study was conducted with 74 established smokers of 1–17 mg Federal Trade Commission (FTC) tar products. The subjects were participating in a five-day inpatient clinical biomarker study during which time they were allowed to smoke their own brand of cigarette whenever they wished. On two separate days, the subjects' breathing pattern was measured using respiratory inductive plethysmography while they smoked one cigarette. This enabled the measurement of the post-puff inhalation volume, exhalation volume, inhalation duration, and exhalation duration for each subject after each puff on two of their own brand of cigarettes

Unidirectional relationship between heroin self-administration and impulsive decision-making in rats

Rationale: There is growing clinical evidence for a strong relationship between drug addiction and impulsivity. However, it is not fully clear whether impulsivity is a pre-existing trait or a consequence of drug abuse. Recent observations in the animal models show that pre-existing levels of impulsivity predict cocaine and nicotine seeking. Whether such relationships also exist with respect to non-stimulant drugs is largely unknown. Objective: We studied the relationship between impulsive choice and vulnerability to heroin taking and seeking. Materials and methods: Rats were selected in the delayed reward task based on individual differences in impulsive choice. Subsequently, heroin intravenous self-administration behaviour was analysed, including acquisition of heroin intake, motivation, extinction and drug- and cue-induced reinstatement. Throughout the entire experiment, changes in impulsive choice were monitored weekly. Results and discussion: High impulsivity did not predict measures of heroin taking. Moreover, high impulsive rats did not differ from low impulsive rats in extinction rates or heroin- and cue-induced reinstatement. However, both groups became more impulsive as heroin self-administration continued. During abstinence, impulsivity levels returned towards baseline (pre-heroin) levels. Our results indicate that, in contrast to psychostimulants, impulsive choice does not predict vulnerability to heroin seeking and taking. Conclusion: These data implicate that different neural mechanisms may underlie the vulnerability to opiate and psychostimulant dependence. Moreover, our data suggest that elevated impulsivity levels as observed in heroin-dependent subjects are a consequence of heroin intake rather than a pre-existing vulnerability trait. © 2011 The Author(s)

Controlled dosing of nicotine via an I ntranasal N icotine A erosol D elivery D evice (INADD)

The present report describes an I ntranasal N icotine A erosol D elivery D evice (INADD) employing an artist's airbrush as aerosolizer and precise, electromechanical control of spray duration. It was designed for the administration of controlled doses of nicotine in a laboratory setting and has been used successfully in over 30 smokers and nonsmokers of both genders. In the present study, nicotine was administered to 12 male smokers at three different doses (0.05 mg, 1.00 mg, and 2.00 mg), and at the same dose (1 mg) on three different occasions. The low dose produced a minimal change in plasma nicotine, while the high dose produced a peak increment of around 16 ng/ml. The medium dose reliably produced a peak increment of around 8–9 ng/ml on all three occasions. Nicotine in plasma showed a sharp rise followed by a slower decline, mimicking the pattern associated with cigarette smoking. Physiological and biochemical responses showed significant dose-response relationships. Subjective reports suggested that aerosol dosing was somewhat aversive, but it is unclear whether this effect is intrinsic to the method or due to other factors. The device described in this report answers the need for a safe and easy means of controlling nicotine dose. Moreover, since nicotine administration via aerosol is novel for both smokers and non-smokers, minimizing the contributions of behavioral tolerance and habituation to the dosing vehicle, it lends itself to the comparison of the pharmacological effects of nicotine between experienced and naive subjects.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46339/1/213_2005_Article_BF02247431.pd

Differential effects of nicotine on alcohol consumption in men and women

Nicotine and alcohol are frequently co-used, suggesting that use of one drug may facilitate use of the other. Furthermore, because men and women differ in their responses to both drugs, it is possible that men and women also differ in their responses to the combination of nicotine and alcohol.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46375/1/213_2006_Article_338.pd