Experienced Withdrawal Symptoms Research Articles

Reduced Binding to Nicotinic Receptors After Nicotine Vaccination: Is the Effect Big Enough to Be Clinically Meaningful?

Reduced Binding to Nicotinic Receptors After Nicotine Vaccination: Is the Effect Big Enough to Be Clinically Meaningful?

Safety and Effectiveness of Dexmedetomidine in the Pediatric Intensive Care Unit (SAD–PICU)

Critically ill children require sedation for comfort and to facilitate mechanical ventilation and interventions. Dexmedetomidine is a newer sedative with little safety data in pediatrics, particularly for therapy lasting longer than 48 h. To quantify the frequency of adverse events and withdrawal syndromes associated with dexmedetomidine and to describe the use of this drug for continuous sedation in critically ill children. In this retrospective study of patients who received dexmedetomidine for sedation in the pediatric intensive care unit, adverse events were assessed with the Naranjo scale to determine the likelihood of association with dexmedetomidine. Interventions in response to adverse events were also recorded. One hundred and forty-four patients (median age 34 months, range 0 - 17.7 years) who underwent a total of 153 treatment courses were included. The mean infusion rate of dexmedetomidine was 0.42 μg/kg per hour (standard deviation 0.17 μg/kg per hour, range 0.05-2 μg/kg per hour). The median duration of therapy was 20.50 h (range 0.75-854.75 h), and 70 infusions (46%) lasted more than 24 h. At least one adverse event was observed in 115 (75%) of the treatment courses. Hypotension (81 [53%]) and bradycardia (38 [25%]) were the most common adverse events and were deemed "probably" attributable to dexmedetomidine in 17 (11%) and 9 (6%) of the treatment courses, respectively. In 55 of the 66 treatment courses with infusions lasting longer than 24 h for which post-infusion data were available, at least one withdrawal symptom was observed; agitation (41 [62%]) and hypertension (22 [33%]) were the most common withdrawal symptoms. Dexmedetomidine was commonly administered for longer than 24 h in the authors' institution. Dexmedetomidine was generally well tolerated; however, the majority of patients experienced withdrawal symptoms. Patients receiving dexmedetomidine for more than 24 h should be monitored for withdrawal following discontinuation, and interventions should be provided if needed. Prospective, controlled studies are needed to characterize the safety of long-term dexmedetomidine therapy in critically ill children.

Insight, Self-esteem, and Coping Skills among Patients with Alcohol Addiction

Purpose: This study was conducted to investigate the related factors of insight, self-esteem, and coping skills and the relationships among them in patients with alcohol addiction. Methods: The participants enrolled in this study were 106 patients from two alcohol treatment hospitals in Gyeonggi Province. Data were collected from May, 12 to 20, 2010 using self-report questionnaires. The instruments were the Hanil Alcohol Insight Scale, Rosenberg Self-esteem Scale, and the Ways of Coping Checklist. Data were analyzed using the SPSS-Win 12.0 program. Results: Among the participants, 24.5% had poor insight, 45.3% fair insight, and 30.2% good insight. Insights of participants who had experienced withdrawal symptoms (t=-3.79, p<.001) and of those not living with family (t=-2.07, p=.041) were higher than those who had not experienced the symptoms and who were not living with family. Self-esteem of participants living with family (F=3.60, p<.001) and of those with better academic backgrounds (F=3.39, p=.021) were higher than those of the other groups. Also, self-esteem showed a positive relation with active coping (r=.34, p<.001). Conclusion: The results of the present study suggest that mental health practitioners need to focus on insight and self-esteem enhancement, coping skill development when treating patients with alcohol addiction.

What Is an “Addiction Memory”?

Imagine a heroin addict. This young man started heroin when he was 18, and took drugs for the next 10 years. He was caught by the police, arrested, convicted, and spent half a year in prison. While there, he went through withdrawal. Afterward, he began to feel better, gained weight, and felt like a new man. He decided he was through with drugs. When he was released from prison, he went back home. While approaching the same subway stop where he’d previously experienced heroin withdrawal symptoms (while trying to score more heroin), he began to sweat and gag. After getting off the subway, he vomited on the tracks. He alleviated these symptoms by injecting heroin. The next day, he experienced intense craving and withdrawal symptoms, and again relieved them by injecting heroin. This cycle repeated itself over the next days, and he was soon re-addicted (O’Brien, 1976). So, why did this person experience withdrawal symptoms at the subway stop when he had been clean and sober for 6 months? The answer lies in the complex interactions of glutamate in the brain. Glutamate is the most common excitatory neurotransmitter …

Alleviating symptoms of withdrawal from an opioid.

IntroductionPatients who are discharged following surgery on an oral opioid, and who have taken the drug for 2 or more weeks often experience withdrawal symptoms when they try to discontinue the drug.Case ReportThree weeks after discharge, a 44-year-old female patient decided to reduce her oxycodone (OxyContin®) dosage from 20 mg three times a day to 20 mg two times a day. She experienced severe withdrawal symptoms.MethodTo assist her in withdrawing from the remainder of the drug, a protocol using ondansetron was developed.ResultsAfter 10 days, the patient was opioid and withdrawal-symptom free.ConclusionUse of ondansetron along with tapering of the opioid was safe and effective in preventing further withdrawal symptoms. This case should stimulate research with a larger, more diverse population including those with both short-term and chronic opioid dependence.

Prospective evaluation of the effects of anxiety sensitivity and state anxiety in predicting acute nicotine withdrawal symptoms during smoking cessation.

The current investigation explored the main and interactive effects of anxiety sensitivity (AS) and state anxiety in predicting acute nicotine withdrawal symptoms experienced during the initial 14 days of smoking cessation. Participants included 123 adult daily smokers (84 women; Mage = 45.93 years, SD = 10.34) undergoing psychosocial-pharmacological cessation treatment. Results indicated that after controlling for the effects of participant sex and nicotine dependence, state anxiety but not AS significantly predicted initial levels of nicotine withdrawal symptoms. Results also demonstrated that both state anxiety and AS were significantly related to the change in nicotine withdrawal symptoms over time. Finally, our results revealed a significant interaction between AS and state anxiety. Specifically, higher levels of AS were associated with a stronger relation between state anxiety and nicotine withdrawal symptoms experienced during the cessation attempt. Results suggest that among high AS persons, state anxiety may be more relevant, compared to those low in AS, in regard to experiencing withdrawal symptoms as more intense during the early phases of quitting.

Recognition of Problem Drinking among Young Adult Prisoners

Alcohol is a preventable cause of illness, offending and other adversities worldwide. Prisoners are especially vulnerable. The aim of this study was to test the hypotheses that younger adult male prisoners are more likely to be hazardous drinkers than their older peers, but less likely to recognize this. The study cohort comprised 100 male prisoners aged 18-20 years and 157 aged 21 and over, who were interviewed and completed standard alcohol and drug questionnaires just after reception into prison. It was found that younger men were significantly more likely to be hazardous drinkers than their older peers but less likely to recognise this, even at scores on the Alcohol Use Disorders Identification Test (AUDIT) indicating dependency. They were also less likely to experience withdrawal symptoms, the main factor associated with problem drinking recognition at any age. Younger prisoners were less likely to be depressed, more likely to rate their social support as good and less likely to be dependent drug users. We conclude that reliance on younger prisoners to recognise their hazardous drinking would identify about one-fifth of them. With a lower likelihood of withdrawal symptoms than older men, they are probably still metabolizing alcohol more effectively. Given their similarities to older prisoners in terms of any previous imprisonment and likely personality disorder, formal screening for hazardous drinking might prevent decline into problem drug use, depression, reoffending, re-imprisonment, and social disconnection.

Use of methadone for prevention of opioid withdrawal in critically ill children.

Opioids are commonly administered to critically ill children for analgesia and sedation, but many patients experience opioid withdrawal upon discontinuation. The authors' institution developed a protocol for using methadone to prevent opioid withdrawal in children who have received morphine by continuous IV infusion for 5 days or longer in the pediatric intensive care unit (PICU). The primary objectives were to determine if opioids were tapered according to the protocol and to determine the conversion ratio for IV morphine to oral methadone that was used. Secondary objectives were to describe the methadone dosage used and the clinical outcomes, to evaluate adjustments to methadone dosing, and to report the incidence of adverse effects. A retrospective analysis of charts was conducted for pediatric patients who had received morphine by continuous IV infusion for 5 days or longer followed by methadone in the PICU between May 2008 and August 2009. Validated scoring systems (the Withdrawal Assessment Tool and the State Behavioral Scale) were used to assess symptoms of withdrawal and degree of sedation, respectively. Forty-three patients were included in the study, with median age of 8 months (range 0.25-201 months). For 31 patients (72%), the protocol was not used, and there were no patients for whom the protocol was followed to completion. The median duration of weaning was 10 days (range 0-91 days). The conversion ratio for IV morphine to oral methadone was 1:0.78 for anticipated 5-day weaning and 1:0.98 for anticipated 10-day weaning. During the first 10 days of weaning, 18 patients (42%) experienced withdrawal symptoms. The methadone dose was increased for 11 (26%) of the 43 patients. Patients were sedated for a median of 1 day (range 0-9 days), were comfortable for a median of 6.5 days (range 1-64 days), and were agitated for a median of 2.5 days (range 0-23 days). Naloxone was required for 2 patients. The institution's methadone protocol was not followed consistently during the study period, and practices for transitioning from morphine by continuous IV infusion to methadone with tapering were also inconsistent. Further studies are needed to determine the optimal conversion ratio for morphine to methadone and the optimal tapering regimen to minimize withdrawal symptoms and adverse events.

Development of the Caffeine Withdrawal Symptom Questionnaire: Caffeine withdrawal symptoms cluster into 7 factors

BackgroundHabitual caffeine consumers who abstain from caffeine experience withdrawal symptoms such as headache, fatigue, difficulty concentrating, mood disturbances, and flu-like symptoms (Juliano and Griffiths, 2004). The caffeine withdrawal syndrome has been documented across many experimental studies; however, little is known about how withdrawal symptoms co-vary during a discrete episode. Furthermore, a validated measure of caffeine withdrawal is lacking. ObjectiveTo develop, evaluate, and reduce a 23-item measure of caffeine withdrawal symptoms; the Caffeine Withdrawal Symptom Questionnaire (CWSQ), to a set of composite variables. MethodsCaffeine consumers (N=213) completed the CWSQ after 16h of caffeine abstinence. A subset of participants also completed the CWSQ during a preceding baseline period and/or after double-blind consumption of caffeinated coffee. ResultsPrincipal components analysis resulted in a solution comprised of 7-factors: 1. Fatigue/drowsiness; 2. Low alertness/difficulty concentrating; 3. Mood disturbances; 4. Low sociability/motivation to work; 5. Nausea/upset stomach; 6. Flu-like feelings; and 7. Headache. With the exception of nausea/upset stomach, the CWSQ total score and individual composite scores were significantly greater during caffeine abstinence relative to both baseline and double-blind consumption of caffeinated coffee, thereby demonstrating sensitivity of the measure. Compared to non-daily coffee consumers, daily consumers had greater increases in total withdrawal, fatigue/drowsiness, low alertness/difficulty concentrating, mood disturbances, and headache. ConclusionsFuture directions include replication, assessment on a clinical population, and further examination of psychometric properties of the CWSQ. The CWSQ should facilitate the assessment and diagnosis of caffeine withdrawal and increase our knowledge of the caffeine withdrawal syndrome.

The Translation of Substance Dependence Criteria to Food-Related Behaviors: Different Views and Interpretations

The Translation of Substance Dependence Criteria to Food-Related Behaviors: Different Views and Interpretations

Akathisia Induced by Gabapentin Withdrawal

To report a case of akathisia in a patient with type 2 diabetes after abrupt discontinuation of gabapentin. A 76-year-old female with type 2 diabetes was admitted for change in mental status, agitation, and restless limb movements. She had been taking gabapentin 3600 mg daily for approximately 1 month for diabetic neuropathy. Her other home medications were glyburide 10 mg twice daily, oxycodone/acetaminophen 5 mg/325 mg every 6 hours as needed for leg pain, and zolpidem 5 mg at bedtime. She had taken none of these drugs for 4 days prior to admission because she was unable to have the prescriptions refilled. Subsequently, the patient exhibited repeated arm and leg motions in response to an inner restlessness. Upon admission to the emergency department, she was agitated and restless; all vital signs and results of laboratory studies were within normal limits. Gabapentin was restarted at the original dosage and the symptoms resolved within 8 hours. Because the patient developed lethargy, the gabapentin dosage was reduced and titrated to the original level over 2 days. After 3 days, the patient was well oriented and experienced no further symptoms. She was discharged on the original dosage of gabapentin. To our knowledge, this is the first reported cases of akathisia induced by gabapentin withdrawal. Available case reports suggest that gabapentin withdrawal can occur at doses ranging from 400-8000 mg/day. Patients experienced symptoms similar to those that develop with benzodiazepine withdrawal and were taking gabapentin for as little as 3 weeks to as long as 5 years. This is the first case report to describe akathisia induced by gabapentin withdrawal. The Naranjo probability scale revealed a probable relationship between akathisia and gabapentin withdrawal. If gabapentin discontinuation is desired, it is prudent to gradually taper the dose to avoid withdrawal symptoms, which may occur after as little as 1 month of treatment. Should the patient experience withdrawal symptoms, the optimal treatment is to restart gabapentin.

Abrupt opium discontinuation has no significant triggering effect on acute myocardial infarction

A deleterious effect of withdrawal symptoms due to abrupt discontinuation of opium on the cardiovascular system is one of the recent interesting topics in the cardiovascular field. The current study hypothesized that the withdrawal syndrome due to discontinuing opium might be an important trigger for the appearance of acute myocardial infarction. Eighty-one opium-addicted individuals who were candidates for cardiovascular clinical evaluation and consecutively hospitalized in the coronary care unit (CCU) ward of Shafa Hospital in Kerman between January and July 2009 were included in the study and categorized in the case group, including patients experiencing withdrawal symptoms within 6-12 h after the reduced or discontinued use of opium according to the Diagnostic and Statistical Manual of Mental Disorders-revised IV version (DSM-IV-R) criteria for opium dependence and withdrawal, and the control group, without opium withdrawal symptoms. The appearance of acute myocardial infarction was compared between the two groups using multivariable regression models. Acute myocardial infarction occurred in 50.0% of those with withdrawal symptoms and in 45.1% of patients without evidence of opium withdrawal (P = 0.669). Multivariable analysis showed that opium withdrawal symptoms were not a trigger for acute myocardial infarction adjusting for demographic characteristics, marital status, education level and common coronary artery disease risk profiles [odds ratio (OR) = 0.920, 95% confidence interval (CI) = 0.350-2.419, P = 0.866]. Also, daily dose of opium before reducing or discontinuing use did not predict the appearance of myocardial infarction in the presence of confounder variables (OR = 0.975, 95% CI = 0.832-1.143, P = 0.755). Withdrawal syndrome due to abrupt discontinuation of opium does not have a triggering role for appearance of acute myocardial infarction.

Factors Associated with Self-Rated Benzodiazepine Addiction among Community-Dwelling Seniors

Long-term use of benzodiazepines carries considerable personal consequences such as memory loss and functional impairment. In addition, use over time may bring about dependence and habituation thus leading older persons to believe they cannotdiscontinue the drug and to experience withdrawal symptoms should its use suddenly cease. The frequency of such negative consequences remains unclear. The purpose of this study is to determine the prevalence of self-rated addiction among older persons and its associated factors. Face-to-face computer-assisted interviews were conducted in the homes of 2,785 persons aged 65 years and over, randomly selected from across the Province of Quebec, Canada. Of the 707 users of benzodiazepines, 43% considered themselves addicted. They were more likely to be 75 years or over, to suffer from panic disorder, to believe that health professionals are ready and available to discuss emotional problems with them, and to be less than satisfied with their social relationships. This study...

Double target concept for smoking cessation

Tobacco use is estimated to be the largest single cause of premature death in the world. Nicotine is the major addictive substance in tobacco products. After cigarette smoking, nicotine quickly acts on its target, nicotinic acetylcholine receptors (nAChRs), which are widely distributed throughout the mammalian central nervous system and are expressed as diverse subtypes on cell bodies, dendrites and/or nerve terminals. Through the nAChRs in brain reward circuits, nicotine alters dopaminergic (DA) neuronal function in the ventral tegmental area (VTA) and increases dopamine release from VTA to nuclear accumbens (NA), which leads to nicotine reward, tolerance and dependence. After quitting smoking, smokers experience withdrawal symptoms, including depression, irritability, difficulty concentrating or sleeping, headache, and tiredness. Recently, evidence has been accumulated to reveal the molecular and cellular mechanisms of nicotine reward, tolerance and dependence. The outcomes of these investigations provide pharmacological basis for smoking cessation. Here, I briefly summarize recent advancements of our understanding of nicotine reward, tolerance and dependence. Based on these understandings, I propose a double target hypothesis, in which nAChRs and dopamine release process are two important targets for smoking cessation. Dysfunction of nAChRs (antagonism or desensitization) is crucial to abolish nicotine dependence and the maintenance of an appropriate level of extracellular dopamine eliminates nicotine withdrawal syndromes. Therefore, the medications simultaneously act on these two targets should have the desired effect for smoking cessation. I discuss how to use this double target concept to interpret recent therapies and to develop new candidate compounds for smoking cessation.

Morphine Sulfate and Naltrexone Hydrochloride Extended Release Capsules in Patients with Chronic Osteoarthritis Pain

Objective: To assess the efficacy and safety of morphine sulfate and naltrexone hydrochloride extended release capsules (EMBEDA®; MS-sNT), which contain morphine sulfate pellets with a sequestered naltrexone core, in treating patients with chronic, moderate-to-severe osteoarthritis (hip or knee) pain. Patients and Methods: This phase 3 study had an enriched-enrollment, randomized-withdrawal, double-blind, multicenter design. Patients (N = 547) were titrated to an effective dose of MS-sNT (20–160 mg/day). Responders (n = 344) were randomized to 12 weeks maintenance with an effective MS-sNT dose or were tapered to placebo over 2 weeks. The primary efficacy measure was the change from baseline (CFB) in diary average-pain scores (0–10 scale, Brief Pain Inventory [BPI]) from randomization to the last 7 days of the maintenance period. Secondary efficacy measures included the remaining BPI scores and Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index. Opioid withdrawal symptoms were assessed by the Clinical Opiate Withdrawal Scale (COWS) and Subjective Opiate Withdrawal Scale (SOWS). The study ran from January 10, 2007 through November 8, 2007. Results: MS-sNT maintained pain control better than placebo (mean CFB, diary average-pain score, −0.2 ± 1.9 vs +0.3 ± 2.1; P = 0.045). Change from baseline for MS-sNT pain-diary score (worst, least, average, current) was superior during the maintenance period visits, weeks 2 to 12 (P < 0.05). WOMAC composite score CFB was superior at most visits. MS-sNT was generally well tolerated, with a typical morphine safety profile. No patient taking MS-sNT as directed experienced withdrawal symptoms. Conclusion: MS-sNT provided effective analgesia in patients with chronic, moderate-to-severe osteoarthritis pain, with a safety profile typical of morphine-containing products. Naltrexone sequestered in MS-sNT had no clinically relevant effect when MS-sNT was taken as directed.

Drug Abuse by Adolescents: General Considerations

1. Ximena Sanchez-Samper, MD* 2. John R. Knight, MD* 1. *Center for Adolescent Substance Abuse Research, Children's Hospital Boston, Boston, Mass After completing this article, readers should be able to: 1. Discuss current trends in adolescent substance use and the specific substances used most commonly among 8th, 10th, and 12th graders. 2. Identify risk and protective factors, including genetic and environmental correlates, for the initiation of substance use in adolescents. 3. Discuss the most common concomitant mental health disorders and how they can affect the course of diagnosis and treatment for substance abuse. 4. Delineate the variety of treatment options available. 5. Describe the role of the pediatrician in educating patients and families on substance abuse prevention; performing screening and initial assessments; and providing support, brief counseling, or referrals for in-depth treatment. Adolescence is a time of physical, emotional, and psychological maturation as well as a period of searching for independence and experimentation. One area of experimentation associated with adolescence is substance use. (1) Although many adolescents experiment with drugs and alcohol from time to time without enduring problems, those who develop the disorders of substance abuse and dependence make substance use a major public health concern. The Monitoring the Future Study (MTFS) is a nationwide survey measuring smoking, drinking, and illicit drug use among nearly 50,000 8th, 10th, and 12th graders in more than 400 secondary schools in the United States each year. (2)(3) According to the 2006 overview of findings from the MTFS, approximately one fifth (21%) of today's 8th graders, more than one third (36%) of 10th graders, and nearly half (48%) of all 12th graders reported using an illicit drug at least once during their lifetimes. Despite a minimum legal age requirement to purchase alcohol, 6% of 8th graders, 19% of the 10th graders, and 30% of the 12th graders self-reported drunkenness during the month prior to being interviewed. (2)(3) Among the problems experienced by adolescents who use alcohol and drugs are …

Withdrawal in adolescent light smokers following 24-hour abstinence

Withdrawal is one of the most important symptoms of nicotine addiction. We examined the extent to which adolescent light smokers experienced withdrawal symptoms when deprived of nicotine for a 24-hr period. A total of 20 adolescents aged 13-17 years who smoked 1-5 cigarettes/day (CPD) refrained from smoking for a 24-hr period. Withdrawal scales were administered, and heart rate was measured at baseline, 12, and 24 hr. Neuropsychological testing was performed at baseline and 24 hr. Participants were divided into two groups: very light smokers (1-3 CPD) and light smokers (4-5 CPD). At 12 hr, very light smokers experienced a decrease in withdrawal symptoms versus light smokers, who reported an increase in symptoms (-2.9 vs. 2.8, p = .02). Similarly, at 24 hr, very light smokers experienced a mean decrease in withdrawal score compared with a mean increase for the light smoker group (-2.2 vs. 5.8, p = .04). We did not find a significant change in heart rate or any differences in participants' scores on the memory or concentration tasks. Based on our findings in this controlled laboratory experiment, adolescent very light smokers did not appear to have significant withdrawal symptoms following abstinence from nicotine. Adolescent light smokers who smoke 4-5 CPD experienced subjective withdrawal symptoms but did not have objective signs of nicotine withdrawal. The stage of smoking in which adolescents are smoking 5 CPD or fewer appears to be a crucial time for studying development of nicotine addiction in teens as they may be transitioning from social smoking to early addiction.

Withdrawal symptoms as a predictor of mortality in patients HIV-infected through drug use and receiving highly active antiretroviral therapy (HAART)

Even in the highly active antiretroviral therapy (HAART) era, individuals HIV-infected through injecting drug use (IDUs) are at increased risk of death due to the burden of competing events such as liver disease, overdose and suicide. The objective of this study was to explore the role which life events’ experience, in particular drug-related events such as detoxification or withdrawal symptoms, may play on the risk of death in HIV-infected IDUs. Our analysis was based on longitudinal data of 296 HIV-infected IDUs from when they started HAART. Data collection included medical records and patient's self-reports detailing, among other information, life events including drug-related problems. Multiple imputations for missing data in the explanatory variables together with Cox models were used to identify predictors of death. During HAART follow-up, 26 deaths occurred, corresponding to 1.8 deaths per 100 person-years. The majority (N=8) were attributable to liver disease while 5 were from unknown causes (found deceased at home or in a car). After adjustment for age and time-dependent viral load (>10,000cp/ml) individuals experiencing withdrawal symptoms had a fivefold increased risk of death with respect to the others. Withdrawal symptoms in IDUs living with HIV reflect physicians’ difficulties in managing their patients’ opioid dependence. Early detection and increasing substitution dosages or switching to a more adequate treatment could prevent possible drug-related deaths.

Nicotine dependence criteria and nicotine withdrawal symptoms in relation to pain among an adult general population sample

Background Evidence has shown that people who have smoked at any point in life have a higher probability of pain than those who have never smoked. The goal of this study was to analyze whether there are associations between nicotine dependence including nicotine withdrawal with pain and the number of pain locations. Methods Data stems from a cross-sectional survey study with a probability sample of residents of a northern German area with 4075 study participants, aged 18–64 years (participation rate 70.2%). Face-to-face in-home computer-aided interviews (Composite International Diagnostic Interview) were used to assess single pain locations, the diagnostic criteria of nicotine dependence, alcohol dependence, depressive, and anxiety disorders according to the Diagnostic and Statistical manual of the American Psychiatric Association (DSM-IV). Results Ever smokers with three or more nicotine dependence criteria after controlling for alcohol dependence, depressive, anxiety disorders, age and gender revealed an odds ratio (OR) of 4.2 (95% confidence interval, CI, 2.0–9.0) compared to ever smokers without nicotine dependence criteria, and ever smokers with four or more nicotine withdrawal symptoms displayed an OR of 3.6 (CI 1.5–8.7) compared to ever smokers who had not experienced withdrawal symptoms. Current smokers who used 20 or more cigarettes per day had an OR of 0.5 (CI 0.3–0.8) of experiencing pain in three or more locations compared to former smokers. Conclusion Nicotine dependence criteria are associated with a higher probability of pain than having no nicotine dependence criteria in this general population sample.

Cannabis reinforcement and dependence: role of the cannabinoid CB1 receptor.

Awareness of cannabis dependence as a clinically relevant issue has grown in recent years. Clinical and laboratory studies demonstrate that chronic marijuana smokers can experience withdrawal symptoms upon cessation of marijuana smoking and have difficulty abstaining from marijuana use. This paper will review data implicating the cannabinoid CB1 receptor in regulating the behavioral effects of Delta(9)-tetrahydrocannobinol (THC), the primary psychoactive component of cannabis, across a range of species. The behavioral effects that will be discussed include those that directly contribute to the maintenance of chronic marijuana smoking, such as reward, subjective effects, and the positive and negative reinforcing effects of marijuana, THC and synthetic cannabinoids. The role of the CB1 receptor in the development of marijuana dependence and expression of withdrawal will also be discussed. Lastly, treatment options that may alleviate withdrawal symptoms and promote marijuana abstinence will be considered.