1
|
Podlasek A, Claire R, Campbell KA, Orton S, Thomson R, Coleman T. Systematic review and meta-analysis investigating nicotine, cotinine and carbon monoxide exposures in people who both smoke and use nicotine replacement therapy. Addiction 2023; 118:2076-2092. [PMID: 37394704 DOI: 10.1111/add.16279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 05/16/2023] [Indexed: 07/04/2023]
Abstract
AIMS To determine effects of concurrent smoking and nicotine replacement therapy (NRT) use on reported heaviness of smoking, nicotine (cotinine) body fluid and exhaled air carbon monoxide (CO) concentrations. METHODS Systematic review and meta-analysis of RCTs, which test interventions permitting concurrent NRT use and smoking and comparing, within participants, outcomes when smoking with those when smoking and using NRT concurrently. Measurements included reported number of cigarettes smoked per day (CPD), body fluid cotinine and expired air CO concentrations. RESULTS Twenty-nine studies were included in the review. Meta-analysis of nine showed that, compared with when solely smoking, fewer cigarettes were smoked daily when NRT was used (mean difference during concurrent smoking and NRT use, -2.06 CPD [95% CI = -3.06 to -1.07, P < 0.0001]). Meta-analysis of seven studies revealed a non-significant reduction in exhaled CO during concurrent smoking and NRT use (mean difference, -0.58 ppm [95% CI = -2.18 to 1.03, P = 0.48]), but in the three studies that tested NRT used in the lead-up to quitting (i.e. as preloading), a similar reduction in exhaled CO was statistically significant (mean difference, -2.54 ppm CO [95% CI = -4.14 to -0.95, P = 0.002]). Eleven studies reported cotinine concentrations, but meta-analysis was not possible because of data reporting heterogeneity; of these, seven reported lower cotinine concentrations with concurrent NRT use and smoking, four reported no differences, and none reported higher concentrations. CONCLUSIONS People who smoke and also use nicotine replacement therapy report smoking less heavily than people who solely smoke. When nicotine replacement therapy is used in the lead-up to quitting (preloading), this reported smoking reduction has been biochemically confirmed. There is no evidence that concurrent smoking and nicotine replacement therapy use result in greater nicotine exposure than solely smoking.
Collapse
Affiliation(s)
- Anna Podlasek
- Centre for Academic Primary Care, University of Nottingham, Nottingham, Nottinghamshire, UK
- Tayside Innovation and MedTech Ecosystem (TIME), University of Dundee, Dundee, Scotland, UK
| | - Ravinder Claire
- National Institute for Health and Care Excellence, London, London City, UK
| | - Katarzyna A Campbell
- Centre for Academic Primary Care, University of Nottingham, Nottingham, Nottinghamshire, UK
| | - Sophie Orton
- Centre for Academic Primary Care, University of Nottingham, Nottingham, Nottinghamshire, UK
| | - Ross Thomson
- Centre for Academic Primary Care, University of Nottingham, Nottingham, Nottinghamshire, UK
| | - Tim Coleman
- Centre for Academic Primary Care, University of Nottingham, Nottingham, Nottinghamshire, UK
| |
Collapse
|
2
|
van der Plas A, Antunes M, Pouly S, de La Bourdonnaye G, Hankins M, Heremans A. Meta-analysis of the effects of smoking and smoking cessation on triglyceride levels. Toxicol Rep 2023; 10:367-375. [PMID: 36926662 PMCID: PMC10011683 DOI: 10.1016/j.toxrep.2023.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 02/21/2023] [Accepted: 03/03/2023] [Indexed: 03/07/2023] Open
Abstract
Smoking increases lipid levels, including triglycerides, leading to increased cardiovascular disease risk. We performed a meta-analysis to quantify the effects of smoking and smoking cessation on triglyceride levels. The PubMed and Scopus databases were searched to identify studies reporting either triglyceride levels in smokers and non-smokers or the effects of smoking cessation on triglyceride levels. Fixed- and random-effects models were used to perform the analyses when three or more studies/comparisons were available. We identified 169 and 21 studies evaluating the effects of smoking and smoking cessation, respectively, on triglyceride levels. Triglyceride levels were 0.50 mmol/L (95% confidence interval: 0.49-0.50 mmol/L) higher in smokers than non-smokers, but the effect differed widely across studies. No statistically significant effect was observed on triglyceride levels between baseline and 6 weeks (mean difference [MD] = 0.02 [-0.09, 0.12] mmol/L), 2 months (MD = 0.03 [-0.21, 0.27] mmol/L), 3 months (MD = 0.08 [-0.03, 0.21] mmol/L), or 1 year (MD = 0.04 [-0.06, 0.14] mmol/L) after quitting. However, a slightly significant decrease in triglyceride levels was observed at 1 month after cessation (MD = -0.15 [-0.15, -0.01] mmol/L). The results of this meta-analysis provide a basis for understanding the effects of smoking and smoking cessation on triglyceride levels, which could have important implications for public health.
Collapse
|
3
|
McKee SA, McRae-Clark AL. Consideration of sex and gender differences in addiction medication response. Biol Sex Differ 2022; 13:34. [PMID: 35761351 PMCID: PMC9235243 DOI: 10.1186/s13293-022-00441-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 06/08/2022] [Indexed: 12/22/2022] Open
Abstract
Substance use continues to contribute to significant morbidity and mortality in the United States, for both women and men, more so than another other preventable health condition. To reduce the public health burden attributable to substances, the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism have identified that medication development for substance use disorder is a high priority research area. Furthermore, both Institutes have stated that research on sex and gender differences in substance use medication development is a critical area. The purpose of the current narrative review is to highlight how sex and gender have been considered (or not) in medication trials for substance use disorders to clarify and summarize what is known regarding sex and gender differences in efficacy and to provide direction to the field to advance medication development that is consistent with current NIH 'sex as a biological variable' (SABV) policy. To that end, we reviewed major classes of abused substances (nicotine, alcohol, cocaine, cannabis, opioids) demonstrating that, sex and gender have not been well-considered in addiction medication development research. However, when adequate data on sex and gender differences have been evaluated (i.e., in tobacco cessation), clinically significant differences in response have been identified between women and men. Across the other drugs of abuse reviewed, data also suggest sex and gender may be predictive of outcome for some agents, although the relatively low representation of women in clinical research samples limits making definitive conclusions. We recommend the incorporation of sex and gender into clinical care guidelines and improved access to publicly available sex-stratified data from medication development investigations.
Collapse
Affiliation(s)
- Sherry A. McKee
- Yale School of Medicine, 2 Church St South, Suite 109, New Haven, CT 06519 USA
| | | |
Collapse
|
4
|
Gendy MNS, Ibrahim C, Sloan ME, Le Foll B. Randomized Clinical Trials Investigating Innovative Interventions for Smoking Cessation in the Last Decade. Handb Exp Pharmacol 2020; 258:395-420. [PMID: 31267165 DOI: 10.1007/164_2019_253] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Every year, billions of dollars are spent treating smoking and related conditions, yet smoking-related morbidity and mortality continue to rise. There are currently only three FDA-approved medications for smoking cessation: nicotine replacement therapy, bupropion, and varenicline. Although these medications increase abstinence rates, most individuals relapse following treatment. This chapter reviews clinical trials published within the past 10 years investigating novel smoking cessation pharmacotherapies. Among these pharmacotherapies, some showed promising results, such as cytisine and endocannabinoid modulators, whereas others failed to produce significant effects. More research is needed to develop drugs that produce higher rates of long-term abstinence and to determine which subgroups of patients benefit from a given treatment.
Collapse
Affiliation(s)
- Marie N S Gendy
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada
| | - Christine Ibrahim
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada
| | - Matthew E Sloan
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada.
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada.
- Addictions Division, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada.
- Division of Brain and Therapeutics, Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.
- Alcohol Research and Treatment Clinic, Centre for Addiction and Mental Health, Toronto, ON, Canada.
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada.
| |
Collapse
|
5
|
Tobacco use during a clinical trial of mecamylamine for alcohol dependence: Medication effects on smoking and associations with reductions in drinking. J Subst Abuse Treat 2018; 94:91-96. [PMID: 30243424 DOI: 10.1016/j.jsat.2018.08.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 08/06/2018] [Accepted: 08/31/2018] [Indexed: 11/22/2022]
Abstract
Mecamylamine is a nicotinic acetylcholine receptor (nAChR) antagonist that was recently used in a clinical trial to treat alcohol use disorder (AUD) in both smokers and non-smokers. The current manuscript reports a reanalysis of data from this clinical trial in which we examine changes in smoking that occurred over the course of the trial. We focused on examining the effects of mecamylamine on smoking and the association between reductions in alcohol use and smoking. Participants were the subgroup of smokers who participated in the clinical trial of mecamylamine (10 mg/day) to treat their AUD (n = 76). Smoking was assessed prior to randomization and tracked throughout the course of the 12-week medication treatment phase. Participants were categorized as treatment responders or non-responders based on their changes in drinking over the course of the clinical trial. Participants showed a reduction in smoking over the course of the clinical trial, but there were no significant differences in smoking outcomes between the mecamylamine and placebo groups. Among moderate/high dependence smokers, those who successfully reduced drinking showed a significant reduction in cigarettes smoked per day over the clinical trial. Mecamylamine had no detectable effect on smoking outcomes. Reductions in alcohol use predicted more favorable smoking outcomes among moderate/high tobacco dependence smokers irrespective of medication condition. The reduction in smoking among patients who decreased their alcohol use responders highlights an opportunity for patients being treated for AUD to reduce their smoking.
Collapse
|
6
|
Bozinoff N, Le Foll B. Understanding the implications of the biobehavioral basis of nicotine addiction and its impact on the efficacy of treatment. Expert Rev Respir Med 2018; 12:793-804. [PMID: 30092681 DOI: 10.1080/17476348.2018.1507736] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Tobacco use remains the leading cause of preventable death in the United States. There are efficacious behavioral and pharmacological options for smoking cessation including three FDA approved therapies - nicotine replacement therapy, varenicline and bupropion. Nevertheless, uptake of smoking cessation treatments continues to be poor and there is a need for novel smoking cessation treatments. Areas covered: This article reviews the biobehavioral basis of nicotine addiction, its implications for smoking cessation treatments, the various neurotransmitter systems involved in nicotine addictive effects, and their potential therapeutic value. Included are discussions around the role of genetic factors in predicting response to pharmacotherapy and what we know about appropriate application of pharmacotherapy and behavioral interventions for tobacco use disorder. The evidence for harm reduction measures in individuals who are not willing or able to quit smoking is also reviewed. Expert commentary: Many neurotransmitter system targets have been investigated as a result of our understanding of the underlying neurobiology of tobacco use disorder, and there remain important targets that have yet to be fully explored. rTMS or combination therapies are proposed as possible novel strategies to improve smoking cessation.
Collapse
Affiliation(s)
- Nikki Bozinoff
- a Department of Family and Community Medicine , University of Toronto , Toronto , Canada.,b Addiction Medicine Service, Acute Care Program , Centre for Addiction and Mental Health , Toronto , Canada
| | - Bernard Le Foll
- a Department of Family and Community Medicine , University of Toronto , Toronto , Canada.,b Addiction Medicine Service, Acute Care Program , Centre for Addiction and Mental Health , Toronto , Canada.,c Department of Pharmacology and Toxicology, Psychiatry, Institute of Medical Sciences , University of Toronto , Toronto , Canada.,d Centre for Addiction and Mental Health , Campbell Family Mental Health Research Institute, CAMH , Toronto , Canada.,e Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health , Toronto , Canada
| |
Collapse
|
7
|
Designing selective modulators for the nicotinic receptor subtypes: challenges and opportunities. Future Med Chem 2018; 10:433-459. [PMID: 29451400 DOI: 10.4155/fmc-2017-0169] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Nicotinic receptors are membrane proteins involved in several physiological processes. They are considered suitable drug targets for various CNS disorders or conditions, as shown by the large number of compounds which have entered clinical trials. In recent years, nonconventional agonists have been discovered: positive allosteric modulators, allosteric agonists, site-specific agonists and silent desensitizers are compounds able to modulate the receptor interacting at sites different from the orthodox one, or to desensitize the receptor without prior opening. While these new findings can further complicate the pharmacology of these proteins and the design and optimization of ligands, they undoubtedly offer new opportunities to find drugs for the many therapeutic indications involving nicotinic receptors.
Collapse
|
8
|
Mohamed TS, Jayakar SS, Hamouda AK. Orthosteric and Allosteric Ligands of Nicotinic Acetylcholine Receptors for Smoking Cessation. Front Mol Neurosci 2015; 8:71. [PMID: 26635524 PMCID: PMC4658446 DOI: 10.3389/fnmol.2015.00071] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 11/06/2015] [Indexed: 12/23/2022] Open
Abstract
Nicotine addiction, the result of tobacco use, leads to over six million premature deaths world-wide per year, a number that is expected to increase by a third within the next two decades. While more than half of smokers want and attempt to quit, only a small percentage of smokers are able to quit without pharmacological interventions. Therefore, over the past decades, researchers in academia and the pharmaceutical industry have focused their attention on the development of more effective smoking cessation therapies, which is now a growing 1.9 billion dollar market. Because the role of neuronal nicotinic acetylcholine receptors (nAChR) in nicotine addiction is well established, nAChR based therapeutics remain the leading strategy for smoking cessation. However, the development of neuronal nAChR drugs that are selective for a nAChR subpopulation is challenging, and only few neuronal nAChR drugs are clinically available. Among the many neuronal nAChR subtypes that have been identified in the brain, the α4β2 subtype is the most abundant and plays a critical role in nicotine addiction. Here, we review the role of neuronal nAChRs, especially the α4β2 subtype, in the development and treatment of nicotine addiction. We also compare available smoking cessation medications and other nAChR orthosteric and allosteric ligands that have been developed with emphasis on the difficulties faced in the development of clinically useful compounds with high nAChR subtype selectivity.
Collapse
Affiliation(s)
- Tasnim S Mohamed
- Department of Pharmaceutical Sciences, College of Pharmacy, Texas A&M Health Sciences Center Kingsville, TX, USA
| | - Selwyn S Jayakar
- Department of Neurobiology, Harvard Medical School Boston, MA, USA
| | - Ayman K Hamouda
- Department of Pharmaceutical Sciences, College of Pharmacy, Texas A&M Health Sciences Center Kingsville, TX, USA ; Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M Health Sciences Center Bryan, TX, USA
| |
Collapse
|
9
|
Hawk LW, Ashare RL, Rhodes JD, Oliver JA, Cummings KM, Mahoney MC. Does Extended Pre Quit Bupropion Aid in Extinguishing Smoking Behavior? Nicotine Tob Res 2015; 17:1377-84. [PMID: 25589680 PMCID: PMC4612343 DOI: 10.1093/ntr/ntu347] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 12/24/2014] [Indexed: 12/26/2022]
Abstract
INTRODUCTION Understanding the mechanisms by which bupropion promotes smoking cessation may lead to more effective treatment. To the extent that reduced smoking reinforcement is one such mechanism, a longer duration of pre quit bupropion treatment should promote extinction of smoking behavior. We evaluated whether 4 weeks of pre quit bupropion (extended run-in) results in greater pre quit reductions in smoking rate and cotinine and, secondarily, greater short-term abstinence, than standard 1 week of pre quit bupropion (standard run-in). METHODS Adult smokers (n = 95; 48 females) were randomized to a standard run-in group (n = 48; 3-week placebo, then 1-week bupropion pre quit) or an extended run-in group (4-week pre quit bupropion; n = 47). Both groups received group behavioral counseling and 7 weeks of post quit bupropion. Smoking rate (and craving, withdrawal, and subjective effects) was collected daily during the pre quit period; biochemical data (cotinine and carbon monoxide) were collected at study visits. RESULTS During the pre quit period, the extended run-in group exhibited a greater decrease in smoking rate, compared to the standard run-in group, interaction p = .03. Cigarette craving and salivary cotinine followed a similar pattern, though the latter was evident only among women. Biochemically verified 4-week continuous abstinence rates were higher in the extended run-in group (53%) than the standard run-in group (31%), p = .033. CONCLUSIONS The extended use of bupropion prior to a quit attempt reduces smoking behavior during the pre quit period and improved short-term abstinence rates. The data are consistent with an extinction-of-reinforcement model and support further investigation of extended run-in bupropion therapy for smoking cessation.
Collapse
Affiliation(s)
- Larry W Hawk
- Department of Psychology, State University of New York at Buffalo, Buffalo, NY; Department of Health Behavior, Roswell Park Cancer Institute, Buffalo, NY;
| | - Rebecca L Ashare
- Department of Psychology, State University of New York at Buffalo, Buffalo, NY; Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Jessica D Rhodes
- Department of Psychology, State University of New York at Buffalo, Buffalo, NY; Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA
| | - Jason A Oliver
- Department of Psychology, State University of New York at Buffalo, Buffalo, NY; Department of Psychiatry, Yale University, New Haven, CT
| | - Kenneth Michael Cummings
- Department of Health Behavior, Roswell Park Cancer Institute, Buffalo, NY; Hollings Cancer Center, Medical University of South Carolina, Charleston, SC
| | - Martin C Mahoney
- Department of Health Behavior, Roswell Park Cancer Institute, Buffalo, NY
| |
Collapse
|
10
|
Elrashidi MY, Ebbert JO. Emerging drugs for the treatment of tobacco dependence: 2014 update. Expert Opin Emerg Drugs 2014; 19:243-60. [PMID: 24654737 DOI: 10.1517/14728214.2014.899580] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Tobacco dependence remains a global epidemic and the largest preventable cause of morbidity and mortality around the world. Smoking cessation has benefits at all ages but remains challenging for several reasons, among which are the complexities of nicotine addiction and limitations of available pharmacotherapies. AREAS COVERED This review summarizes current and emerging pharmacotherapies for the treatment of tobacco dependence, including first- and second-line recommended agents. Medications with alternative primary indications that have been investigated as potential treatments for tobacco dependence are also discussed. Articles reviewed were obtained through searches of PubMed, Ovid MEDLINE, ClinicalTrials.gov and the Pharmaprojects database. EXPERT OPINION Current evidence suggests that the two most effective pharmacotherapies to treat tobacco dependence are varenicline and combination nicotine replacement therapy. Alternative agents investigated demonstrate mixed rates of success in achieving long-term abstinence from smoking. No single pharmacotherapy will serve as a universally successful treatment given the complex underpinnings of tobacco dependence and individuality of smokers. The ultimate goal of tobacco research with respect to pharmacotherapeutic development continues to be providing clinicians with an armamentarium of drugs to choose from allowing for tailoring of treatment for smokers.
Collapse
|
11
|
|
12
|
Nickell JR, Grinevich VP, Siripurapu KB, Smith AM, Dwoskin LP. Potential therapeutic uses of mecamylamine and its stereoisomers. Pharmacol Biochem Behav 2013; 108:28-43. [PMID: 23603417 PMCID: PMC3690754 DOI: 10.1016/j.pbb.2013.04.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 04/01/2013] [Accepted: 04/03/2013] [Indexed: 12/17/2022]
Abstract
Mecamylamine (3-methylaminoisocamphane hydrochloride) is a nicotinic parasympathetic ganglionic blocker, originally utilized as a therapeutic agent to treat hypertension. Mecamylamine administration produces several deleterious side effects at therapeutically relevant doses. As such, mecamylamine's use as an antihypertensive agent was phased out, except in severe hypertension. Mecamylamine easily traverses the blood-brain barrier to reach the central nervous system (CNS), where it acts as a nicotinic acetylcholine receptor (nAChR) antagonist, inhibiting all known nAChR subtypes. Since nAChRs play a major role in numerous physiological and pathological processes, it is not surprising that mecamylamine has been evaluated for its potential therapeutic effects in a wide variety of CNS disorders, including addiction. Importantly, mecamylamine produces its therapeutic effects on the CNS at doses 3-fold lower than those used to treat hypertension, which diminishes the probability of peripheral side effects. This review focuses on the pharmacological properties of mecamylamine, the differential effects of its stereoisomers, S(+)- and R(-)-mecamylamine, and the potential for effectiveness in treating CNS disorders, including nicotine and alcohol addiction, mood disorders, cognitive impairment and attention deficit hyperactivity disorder.
Collapse
Affiliation(s)
- Justin R Nickell
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA.
| | | | | | | | | |
Collapse
|
13
|
Scheidweiler KB, Shakleya DM, Huestis MA. Simultaneous quantification of nicotine, cotinine, trans-3'-hydroxycotinine, norcotinine and mecamylamine in human urine by liquid chromatography-tandem mass spectrometry. Clin Chim Acta 2012; 413:978-84. [PMID: 22394455 PMCID: PMC3319642 DOI: 10.1016/j.cca.2012.02.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 02/10/2012] [Accepted: 02/11/2012] [Indexed: 11/22/2022]
Abstract
BACKGROUND Mecamylamine is a nicotine antagonist under investigation in combination with nicotine replacement for smoking treatment. METHODS A simple, rapid and reliable liquid chromatography tandem mass spectrometry (LCMSMS) method was developed and validated for quantifying nicotine, cotinine, trans-3'-hydroxycotinine, norcotinine and mecamylamine in human urine. Chromatography was performed on a Synergi PolarRP column with a gradient of 0.1% formic acid and 0.1% formic acid in acetonitrile at 0.25 ml/min with an 8-min total runtime. Analytes were monitored by positive mode electrospray ionization and multiple reaction monitoring mass spectrometry. RESULTS Linear dynamic ranges were 1-500 ng/ml for nicotine and norcotinine, 0.5-500 ng/ml for trans-3'-hydroxycotinine, 0.2-500 ng/ml for cotinine, and 0.1-100 ng/ml for mecamylamine; correlation coefficients were consistently greater than 0.99, and all calibrator concentrations were within 20% of target. Extensive endogenous and exogenous interferences were evaluated. At 3 concentrations spanning the linear dynamic range of the assay, mean extraction efficiencies from urine were 55.1-109.1% with analytical recovery (bias) 82.0-118.7% and total imprecision of 0.7-9.1%. Analytes were stable for 24h at room temperature, 72 h at 4 °C, 72 h in autosampler at 15 °C and after three freeze/thaw cycles. CONCLUSION This method is useful for monitoring mecamylamine, nicotine and nicotine metabolites in smoking cessation and other clinical nicotine research.
Collapse
Affiliation(s)
- Karl B. Scheidweiler
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
| | - Diaa M. Shakleya
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
| | - Marilyn A. Huestis
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
| |
Collapse
|
14
|
[Guidelines for smoking cessation - update 2010]. Wien Klin Wochenschr 2011; 123:299-315. [PMID: 21590322 DOI: 10.1007/s00508-011-1571-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 12/27/2010] [Indexed: 12/13/2022]
Abstract
In 2005, the ÖGP (Austrian Society of Pneumology) worked out the first standards of smoking cessation. With many new therapies, it is timely to update the guidelines of smoking cessation. This time all relevant professionals who are active in smoking cessation in Austria worked together in a big consensus process, not only the diverse medical professionals such as internists, pneumologists, or gynecologists but also psychotherapists, psychologists, and nurses. The Austrian standards for smoking cessation is closely related to the Update for smoking cessation 2008 of the USDHHS (US Department of Health and Human Services) and the Cochrane Reports. Ten main recommendations for smoking cessation have been worked out. The guidelines for smoking cessation was reviewed by three international reviewers.
Collapse
|
15
|
Wu CH, Lee CH, Ho YS. Nicotinic acetylcholine receptor-based blockade: applications of molecular targets for cancer therapy. Clin Cancer Res 2011; 17:3533-41. [PMID: 21444681 DOI: 10.1158/1078-0432.ccr-10-2434] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The nicotinic acetylcholine receptor (nAChR) was first characterized in 1970 as a membrane receptor of a neurotransmitter and an ion channel. nAChRs have been shown to be involved in smoking-induced cancer formation in multiple types of human cancer cells. In vitro and in vivo animal studies have shown that homopentameric nAChR inhibitors, such as methyllycaconitine and α-Bgtx, can attenuate nicotine-induced proliferative, angiogenic, and metastatic effects in lung, colon, and bladder cancer cells. Recent publications have shown that α9-nAChR is important for breast cancer formation, and in many in vivo studies, α9-nAChR-specific antagonists (e.g., α-ImI, α-ImI, Vc1.1, RgIA, and It14a) produced an analgesic effect. Vc1.1 functions in a variety of animal pain models and currently has entered phase II clinical trials. For cancer therapy, natural compounds such as garcinol and EGCG have been found to block nicotine- and estrogen-induced breast cancer cell proliferation through inhibition of the α9-nAChR signaling pathway. A detailed investigation of the carcinogenic effects of nAChRs and their specific antagonists would enhance our understanding of their value as targets for clinical translation.
Collapse
Affiliation(s)
- Chih-Hsiung Wu
- Department of Surgery, School of Medicine, and Graduate Institute of Medical Sciences, College of Medicine, Taipei, Taiwan
| | | | | |
Collapse
|
16
|
Hall BJ, Pearson LS, Buccafusco JJ. Effect of administration of the nicotinic acetylcholine receptor antagonist BTMPS, during nicotine self-administration, on lever responding induced by context long after withdrawal. Neuropharmacology 2010; 58:429-35. [DOI: 10.1016/j.neuropharm.2009.09.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 09/14/2009] [Accepted: 09/15/2009] [Indexed: 11/29/2022]
|
17
|
Bacher I, Wu B, Shytle DR, George TP. Mecamylamine - a nicotinic acetylcholine receptor antagonist with potential for the treatment of neuropsychiatric disorders. Expert Opin Pharmacother 2010; 10:2709-21. [PMID: 19874251 DOI: 10.1517/14656560903329102] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Mecamylamine (Inversine), the first orally available antihypertensive agent launched in the 1950s, is rarely used today for hypertension because of its widespread ganglionic side effects at antihypertensive doses (25 - 90 mg/day). However, more recent clinical studies suggest that mecamylamine is effective at much lower doses for blocking the central and peripheral effects of nicotine. Pharmacologically, mecamylamine has been well characterized as a nonselective and noncompetitive antagonist of nicotinic acetylcholine receptors (nAChRs). Because mecamylamine easily crosses the blood - brain barrier at relatively low doses (2.5 - 10 mg), it has been used by several research groups over the past two decades investigating the role of central nAChRs in the etiology and treatment of various neuropsychiatric disorders, including addiction disorders, Tourette's syndrome, schizophrenia and various cognitive and mood disorders. Two independent Phase II clinical trials recently confirmed mecamylamine's hypothesized antidepressant activity and suggest that it may be effective as an augmentation pharmacotherapy for SSRI treatment resistant major depression. These areas of investigation for mecamylamine are reviewed and recommendations for future research directions are proposed.
Collapse
Affiliation(s)
- Ingrid Bacher
- University of Toronto, Department of Psychiatry, Faculty of Medicine, Toronto, Canada.
| | | | | | | |
Collapse
|
18
|
Jupp B, Lawrence AJ. New horizons for therapeutics in drug and alcohol abuse. Pharmacol Ther 2010; 125:138-68. [DOI: 10.1016/j.pharmthera.2009.11.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Accepted: 11/03/2009] [Indexed: 11/25/2022]
|
19
|
Edens E, Massa A, Petrakis I. Novel pharmacological approaches to drug abuse treatment. Curr Top Behav Neurosci 2010; 3:343-86. [PMID: 21161760 DOI: 10.1007/7854_2009_29] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The field of pharmacologic addiction treatment is expanding rapidly. While there are currently several FDA-approved medications for nicotine, alcohol, and opiate dependence, research into novel pharmacological approaches for these and additional substances is legion. Each drug of abuse, while sharing a common final neural pathway of increasing dopaminergic tone, has unique and individual characteristics that are important in developing improved and varied treatments. In this chapter, we discuss such research and present the neurobiological underpinnings of these explorations. In general, addiction treatment is focused on four areas: (1) reducing withdrawal discomfort, (2) diminishing cravings, (3) blocking rewarding effects of the drug, and (4) treating comorbidities, such as depression or ADHD. We present current ideas in pharmacologic research for nicotine, alcohol, cannabis, stimulants, and opiates.
Collapse
Affiliation(s)
- Ellen Edens
- West Haven Veterans Administration Medical Center, West Haven, CT 06516, USA
| | | | | |
Collapse
|
20
|
McKee SA, Weinberger AH, Harrison ELR, Coppola S, George TP. Effects of the nicotinic receptor antagonist mecamylamine on ad-lib smoking behavior, topography, and nicotine levels in smokers with and without schizophrenia: a preliminary study. Schizophr Res 2009; 115:317-24. [PMID: 19700263 PMCID: PMC2784178 DOI: 10.1016/j.schres.2009.07.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 07/21/2009] [Accepted: 07/27/2009] [Indexed: 10/20/2022]
Abstract
Individuals with schizophrenia have higher plasma nicotine levels in comparison to non-psychiatric smokers, even when differences in smoking are equated. This difference may be related to how intensely cigarettes are smoked but this has not been well studied. Mecamylamine (MEC), a non-competitive nicotinic acetylcholine receptor (nAChR) antagonist, which has been shown to increase ad-lib smoking and to affect smoking topography, was used in the current study as a pharmacological probe to increase our understanding of smoking behavior, smoking topography, and resulting nicotine levels in smokers with schizophrenia. This preliminary study used a within-subject, placebo-controlled design in smokers with schizophrenia (n=6) and healthy control smokers (n=8) to examine the effects of MEC (10mg/day) on ad-lib smoking behavior, topography, nicotine levels, and tobacco craving across two smoking deprivation conditions (no deprivation and 12-h deprivation). MEC, compared to placebo, increased the number of cigarettes smoked and plasma nicotine levels. MEC increased smoking intensity and resulted in greater plasma nicotine levels in smokers with schizophrenia compared to controls, although these results were not consistent across deprivation conditions. MEC also increased tobacco craving in smokers with schizophrenia but not in control smokers. Our results suggest that antagonism of high-affinity nAChRs in smokers with schizophrenia may prompt compensatory smoking, increasing the intensity of smoking and nicotine exposure without alleviating craving. Further work is needed to assess whether nicotine levels are directly mediated by how intensely the cigarettes are smoked, and to confirm whether this effect is more pronounced in smokers with schizophrenia.
Collapse
Affiliation(s)
- Sherry A. McKee
- Division of Substance Abuse, Department of Psychiatry, Yale University School of Medicine 2 Church St. South, Suite 109, New Haven, CT 06519
| | - Andrea H. Weinberger
- Division of Substance Abuse, Department of Psychiatry, Yale University School of Medicine 34 Park St., S-211, New Haven, CT 06519
| | - Emily L. R. Harrison
- Division of Substance Abuse, Department of Psychiatry, Yale University School of Medicine 2 Church St. South, Suite 109, New Haven, CT 06519
| | - Sabrina Coppola
- Division of Substance Abuse, Department of Psychiatry, Yale University School of Medicine 2 Church St. South, Suite 109, New Haven, CT 06519
| | - Tony P. George
- Schizophrenia Program and Division of Addiction Psychiatry, Centre for Addiction and Mental Health (CAMH) and Department of Psychiatry, University of Toronto, 250 College Street, Room CS 734, Toronto, Ontario, Canada M5T 1R8
| |
Collapse
|
21
|
Janes AC, Frederick BD, Richardt S, Burbridge C, Merlo-Pich E, Renshaw PF, Evins AE, Fava M, Kaufman MJ. Brain fMRI reactivity to smoking-related images before and during extended smoking abstinence. Exp Clin Psychopharmacol 2009; 17:365-73. [PMID: 19968401 PMCID: PMC3742373 DOI: 10.1037/a0017797] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Reactivity to smoking-related cues may play a role in the maintenance of smoking behavior and may change depending on smoking status. Whether smoking cue-related functional MRI (fMRI) reactivity differs between active smoking and extended smoking abstinence states currently is unknown. We used fMRI to measure brain reactivity in response to smoking-related versus neutral images in 13 tobacco-dependent subjects before a smoking cessation attempt and again during extended smoking abstinence (52 +/- 11 days) aided by nicotine replacement therapy. Prequit smoking cue induced fMRI activity patterns paralleled those reported in prior smoking cue reactivity fMRI studies. Greater fMRI activity was detected during extended smoking abstinence than during the pre-quit [corrected] assessment subcortically in the caudate nucleus and cortically in prefrontal (BA 6, 8, 9, 10, 44, 46), [corrected] primary somatosensory (BA 1, 2, 3), temporal (BA 22), [corrected] parietal (BA 5, 7, 40), occipital (BA 17, 18), [corrected] and posterior cingulate (BA 31) cortex. These data suggest that during extended smoking abstinence, fMRI reactivity to smoking versus neutral stimuli persists in brain areas involved in attention, somatosensory processing, motor planning, and conditioned cue responding. In some brain regions, fMRI smoking cue reactivity is increased during extended smoking abstinence in comparison to the prequit state, which may contribute to persisting relapse vulnerability.
Collapse
Affiliation(s)
- Amy C. Janes
- Brain Imaging Center, McLean Hospital, Belmont, MA,Correspondence: Amy C. Janes, Ph.D., Brain Imaging Center, 115 Mill Street, McLean Hospital, Belmont, MA 02478, TEL: (617) 855-3244,
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Mechanism-based medication development for the treatment of nicotine dependence. Acta Pharmacol Sin 2009; 30:723-39. [PMID: 19434058 DOI: 10.1038/aps.2009.46] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Tobacco use is a global problem with serious health consequences. Though some treatment options exist, there remains a great need for new effective pharmacotherapies to aid smokers in maintaining long-term abstinence. In the present article, we first discuss the neural mechanisms underlying nicotine reward, and then review various mechanism-based pharmacological agents for the treatment of nicotine dependence. An oversimplified hypothesis of addiction to tobacco is that nicotine is the major addictive component of tobacco. Nicotine binds to alpha4beta2 and alpha7 nicotinic acetylcholine receptors (nAChRs) located on dopaminergic, glutamatergic and GABAergic neurons in the mesolimbic dopamine (DA) system, which causes an increase in extracellular DA in the nucleus accumbens (NAc). That increase in DA reinforces tobacco use, particularly during the acquisition phase. Enhanced glutamate transmission to DA neurons in the ventral tegmental area appears to play an important role in this process. In addition, chronic nicotine treatment increases endocannabinoid levels in the mesolimbic DA system, which indirectly modulates NAc DA release and nicotine reward. Accordingly, pharmacological agents that target brain acetylcholine, DA, glutamate, GABA, or endocannabonoid signaling systems have been proposed to interrupt nicotine action. Furthermore, pharmacokinetic strategies that alter plasma nicotine availability, metabolism and clearance also significantly alter nicotine's action in the brain. Progress using these pharmacodynamic and pharmacokinetic agents is reviewed. For drugs in each category, we discuss the mechanistic rationale for their potential anti-nicotine efficacy, major findings in preclinical and clinical studies, and future research directions.
Collapse
|
23
|
Abstract
Cigarette smoking is a tenacious addiction that is maintained to a significant extent by the reinforcing effects of nicotine. An emerging theme in smoking cessation treatment is the development of methods for interfering with these reinforcing effects. By attenuating nicotine reinforcement, treatments may enhance a smoker's chances of successfully remaining abstinent. Several treatment approaches will be described, including the use of denicotinized cigarettes, nicotine vaccines, nicotinic receptor agonists and antagonists, and modulators of brain reinforcement processes. These techniques highlight the numerous sites along the path between the cigarette and the brain that can be targeted for intervention. In addition to unimodal therapies, treatment combinations will be discussed that might more effectively block cigarette reward and thereby further enhance smoking abstinence.
Collapse
Affiliation(s)
- Jed E Rose
- Duke University Medical Center, Durham, NC, USA.
| |
Collapse
|
24
|
Buchhalter AR, Fant RV, Henningfield JE. Novel pharmacological approaches for treating tobacco dependence and withdrawal: current status. Drugs 2008; 68:1067-88. [PMID: 18484799 DOI: 10.2165/00003495-200868080-00005] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Increasing the diversity and availability of medications for the treatment of tobacco dependence and/or withdrawal, to aid in the achievement of smoking cessation, is crucial to meet the diverse needs of tobacco users. Despite a general awareness that smoking is harmful and widespread interest in smoking cessation, nearly 50 million adults in the US and 1.3 billion worldwide continue to smoke. Nicotine replacement therapies are effective in the treatment of tobacco dependence and withdrawal, but do not meet the needs of all tobacco users. Improvement of tobacco dependence and/or withdrawal treatments is likely to rely on novel pharmacological approaches that include new chemical entities and new formulations of current drugs. In addition, new indications for treating tobacco dependence and withdrawal show promise for reducing tobacco use and associated disease. This article focuses on a range of novel pharmacological approaches for the treatment of tobacco dependence and/or withdrawal, including oral and pulmonary nicotine delivery and the following non-nicotinic medications: antidepressants, an alpha4beta2 nicotine partial agonist, an alpha2-noradrenergic agonist, cytochrome P450 (CYP) 2A6 inhibitors, opioid antagonists and GABAergic medications. In addition to existing medications, this article addresses novel medications in the clinical development stage and those that have been evaluated previously. Novel medications in the clinical development stage include at least three nicotine vaccines and the cannabinoid receptor acting drug rimonabant. Medications evaluated previously include lobeline, mecamylamine and an anticholinergic drug regimen comprising atropine, scopolamine and chlorpromazine. Having not been approved by major drug regulatory authorities for the treatment of tobacco dependence and/or withdrawal, these medications have been evaluated in an experimental capacity.
Collapse
|
25
|
Karam-Hage M, Cinciripini PM. Pharmacotherapy for tobacco cessation: nicotine agonists, antagonists, and partial agonists. Curr Oncol Rep 2008; 9:509-16. [PMID: 17991361 DOI: 10.1007/s11912-007-0072-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Nicotine replacement therapies (NRT) were the main pharmacologic option for treatment of nicotine dependence until the early 1990s, when controlled clinical trials confirmed the efficacy of bupropion, the first treatment not based on nicotine. Varenicline, a partial agonist at nicotine receptors, gained US regulatory approval in 2006 for smoking cessation. Although these agents are all effective for nicotine dependence, their efficacy rates vary compared with placebo (overall OR for NRT efficacy, 1.77; for bupropion, 1.94; for varenicline, 3.09). Each of these treatments has a place, sometimes in combinations with other agents, in cancer patients who continue to smoke. Our initial experience with varenicline has been encouraging. Bupropion has specific advantages for cancer patients, including increased energy, low risk for nausea, and decreased weight gain from quitting.
Collapse
Affiliation(s)
- Maher Karam-Hage
- Division of Cancer Prevention, Department of Behavioral Science, The University of Texas M.D. Anderson Cancer Center, 1155 Pressler Street, CPB, Unit 1330, Houston, TX 77030, USA.
| | | |
Collapse
|
26
|
Abstract
AIM To evaluate the incremental efficacy of starting nicotine patch treatment prior to quitting compared to the current regimen of starting patch treatment on the target quit day. DESIGN AND MEASUREMENTS Meta-analysis of four eligible studies using pre-cessation patch treatment, located by database search and contacts with cessation researchers. The studies all compared starting treatment with nicotine patch prior to the target quit date to starting active treatment at the quit date, some in the context of concurrent mecamylamine treatment. The primary end-point for the analysis was continuous abstinence for at least 28 days assessed at 6 weeks following quit day; 6-month outcomes were also examined. FINDINGS Compared to starting active patch treatment on quit day, pre-cessation treatment with nicotine patches was found to double the odds of quitting. This was true both at 6 weeks [pooled odds ratio (OR) = 1.96, 95% confidence interval (CI): 1.31-2.93] and 6 months (pooled OR = 2.17, 95% CI: 1.46-3.22) treatment outcomes. Mecamylamine co-treatment did not modify these effects. CONCLUSIONS Across the four studies analyzed, pre-cessation patch treatment was found to produce a robust increase in quit rates compared to current regimens starting patch at quit day. Pre-cessation patch use represents a promising innovation in smoking cessation therapy with potential beneficial implications for improved public health by further increasing quitting success.
Collapse
|
27
|
Rose JE. New findings on nicotine addiction and treatment. NEBRASKA SYMPOSIUM ON MOTIVATION. NEBRASKA SYMPOSIUM ON MOTIVATION 2008; 55:131-41. [PMID: 19013942 DOI: 10.1007/978-0-387-78748-0_8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Jed E Rose
- Center for Nicotine and Smoking Cessation Research, Duke University Medical Center, 2424 Erwin Road, Suite 210, Durham, NC 27705, USA.
| |
Collapse
|
28
|
West R. Access to data from clinical trials sponsored by pharmaceutical companies. Addiction 2007; 102:682-3. [PMID: 17493100 DOI: 10.1111/j.1360-0443.2007.01799.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
29
|
Abstract
BACKGROUND Mecamylamine is a nicotine antagonist (that is it blocks the effect of nicotine). The rationale for its use in smoking cessation is that it may block the rewarding effect of nicotine and thus reduce the urge to smoke. OBJECTIVES The objective of this review was to determine the effectiveness of mecamylamine in promoting smoking cessation, either alone or in combination with nicotine replacement therapy. SEARCH STRATEGY We searched the Cochrane Tobacco Addiction Group trials register. SELECTION CRITERIA Randomised trials of mecamylamine, either alone or in combination with nicotine replacement therapy, which reported smoking cessation rates at least six months after intervention. DATA COLLECTION AND ANALYSIS We extracted data in duplicate on the type of subjects, the dose and duration of the mecamylamine and nicotine treatments, side-effects of treatment, the outcome measures, method of randomisation, and completeness of follow-up. The main outcome measure was sustained abstinence from smoking (biochemically validated) after at least six months follow-up in patients smoking at baseline. Smokers lost to follow-up were regarded as being continuing smokers. Because of the preliminary nature of available data, we did not perform meta-analysis but report the results narratively. MAIN RESULTS We identified two studies, both from the same investigators. In a study of 48 volunteers, a combination of mecamylamine plus nicotine patch was more effective than nicotine patch alone (abstinence rate at one year 37.5% vs 4.2%). In a second study, 80 volunteers were treated for four weeks prior to cessation with one of four treatments: 1. Nicotine patch plus mecamylamine capsules 2. Nicotine alone 3. Mecamylamine alone 4. No active drug. All four groups received combination treatment with nicotine and mecamylamine after the scheduled quit date. The abstinence rates in these four groups were respectively 40%, 20%, 15% and 15%. The higher abstinence rate in the group treated with combination therapy was not statistically significant. The authors reported a statistically significant benefit of mecamylamine using Kaplan-Meier survival analysis. In the doses used, mecamylamine was well tolerated, although up to 40% of subjects required reductions in dose, usually because of constipation. REVIEWER'S CONCLUSIONS Data from two small studies suggest that the combination of nicotine and mecamylamine may be superior to nicotine alone in promoting smoking cessation. However, these results require confirmation in larger studies before the treatment can be recommended clinically.
Collapse
Affiliation(s)
- T Lancaster
- ICRF General Practice Research Group, Division of Public Health and Primary Health Care, Institute of Health Sciences, Old Road, Headington, Oxford, UK, OX3 7LF.
| | | |
Collapse
|