Cannabis Smoking in 2015: A Concern for Lung Health?

Effects of cannabis smoking on the respiratory system: A state-of-the-art review

The diminished perception of the health risks associated with the consumption of cannabis (marijuana) lead to a progressive increase in its inhalational use in many countries. Cannabis can be smoked through the use of joints, spliffs and blunts, and it can be vaporised with the use of hookah or e-cigarettes. Delta-9 tetrahydrocannabinol (THC) is the main psychoactive component of cannabis smoke but contains numerous other substances. While the recreational use of cannabis smoking has been legalised in several countries, its health consequences have been underestimated and undervalued. The purpose of this review is to critically review the impact of cannabis smoke on the respiratory system. Cannabis smoke irritates the bronchial tree and is strongly associated with symptoms of chronic bronchitis, with histological signs of airway inflammation and remodelling. Altered fungicidal and antibacterial activity of alveolar macrophages, with greater susceptibility to respiratory infections, is also reported. The association with invasive pulmonary aspergillosis in immunocompromised subjects is particularly concerning. Although cannabis has been shown to produce a rapid bronchodilator effect, its chronic use is associated with poor control of asthma by numerous studies. Cannabis smoking also represents a risk factor for the development of bullous lung disease, spontaneous pneumothorax and hypersensitivity pneumonitis. On the other hand, no association with the development of chronic obstructive pulmonary disease was found. Finally, a growing number of studies report an independent association of cannabis smoking with the development of lung cancer. In conclusion, unequivocal evidence established that cannabis smoking is harmful to the respiratory system. Cannabis smoking has a wide range of negative effects on respiratory symptoms in both healthy subjects and patients with chronic lung disease. Given that the most common and cheapest way of assumption of cannabis is by smoking, healthcare providers should be prepared to provide counselling on cannabis smoking cessation and inform the public and decision-makers.

Associations for subgroups of E-cigarette, cigarette, and cannabis use with asthma in a population sample of California adolescents

Knowledge about the respiratory health consequences of adolescents' use of tobacco products with cannabis remains limited. We studied whether e-cigarettes, combustible cigarettes, and cannabis were independently associated with asthma in a population-based sample of 150,634 public high school students (10th and 12th graders), drawn in a two-stage design to be representative of the state of California in 2019-2020. Measures were obtained for use of e-cigarettes, combustible cigarettes, and cannabis; motives for use (three substances); method of use (for cannabis); ever being diagnosed with asthma; and having an asthma attack in past 12 months. Cross-classification indicated Nonuse for 64% of the sample; 15% Dual E-cigarette/Cannabis Use; 10% Exclusive Cannabis Use; 5% Exclusive E-cigarette Use; and 5% Triple Use. Multinomial logistic regression with a three-level criterion variable, controlling for age, sex, parental education, race/ethnicity, and three types of household use showed that compared with Nonuse, odds of Lifetime Asthma (vs. Never Had) was elevated for Triple Use (AOR = 1.14, CI 1.06-1.24), Dual E-cigarette/Cannabis Use (1.17, 1.12-1.23), Exclusive Cannabis Use (1.17, 1.11-1.23), and Exclusive E-cigarette Use (1.10, 1.02-1.18). Similar results were noted for Recent Asthma. Among persons who had used cannabis, 88% of the Triple group and 74% of the Dual E-cigarette/Cannabis group reported both smoking and vaping cannabis. Thus, co-occurrence of e-cigarette and cannabis use was a common pattern among adolescents in this study, and subgroups of cannabis and e-cigarette use showed similar associations with asthma. Preventive approaches should highlight the health implications of exclusive or combined e-cigarette and cannabis use.

Impact of Marijuana Smoking on COPD Progression in a Cohort of Middle-Aged and Older Persons

Background

Limited data are available regarding marijuana smoking's impact on the development or progression of chronic obstructive pulmonary disease (COPD) in middle-aged or older adults with a variable history of tobacco cigarette smoking.

Methods

We divided ever-tobacco smoking participants in the SubPopulations and InteRmediate Outcomes In COPD Study (SPIROMICS) into 3 groups based on self-reported marijuana use: current, former, or never marijuana smokers (CMSs, FMSs or NMSs, respectively). Longitudinal data were analyzed in participants with ≥2 visits over a period of ≥52 weeks.

Measurements

We compared CMSs, FMSs, and NMSs, and those with varying amounts of lifetime marijuana use. Mixed effects linear regression models were used to analyze changes in spirometry, symptoms, health status, and radiographic metrics; zero-inflated negative binomial models were used for exacerbation rates. All models were adjusted for age, sex, race, baseline tobacco smoking amount, and forced expiratory volume in 1 second (FEV1) %predicted.

Results

Most participants were followed for ≥4 years. Annual rates of change in FEV1, incident COPD, respiratory symptoms, health status, radiographic extent of emphysema or air trapping, and total or severe exacerbations were not different between CMSs or FMSs versus NMSs or between those with any lifetime amount of marijuana use versus NMSs.

Conclusions

Among SPIROMICS participants with or without COPD, neither former nor current marijuana smoking of any lifetime amount was associated with evidence of COPD progression or its development. Because of our study's limitations, these findings underscore the need for further studies to better understand longer-term effects of marijuana smoking in COPD.

Illegal drugs and periodontal conditions

In recent years, the practice of dentistry and periodontology has become complicated by several risk factors, including the treatment of an increasing number of patients with substance use disorder. This review presents an update in the current literature of the impact of illegal drug use on periodontal conditions and their possible effect as risk factors or indicators. The main illegal drugs that may have an impact on periodontal health and conditions are described, including their effect, medical manifestations, risks, and the overall effect on oral health and on the periodontium. Where available, data from epidemiologic studies are analyzed and summarized. The clinical management of periodontal patients using illegal drugs is reported in a comprehensive approach inclusive of the detection of illicit drug users, screening, interviewing and counseling, the referral to treatment, and the dental and periodontal management. With regard to the impact of illegal substance use on periodontal conditions, there is moderate evidence that regular long-term use of cannabis is a risk factor for periodontal disease, manifesting as a loss of periodontal attachment, deep pockets, recessions, and gingival enlargements. Limited evidence also shows that the use of cocaine can cause a series of gingival conditions that mostly presents as chemical induced-traumatic lesions (application of cocaine on the gingiva) or necrotizing ulcerative lesions. There is a scarcity of data regarding the impact of other drug use on periodontal health. There is evidence to suggest that regular long-term use of cannabis is a risk factor for periodontal disease and that the use of cocaine can cause a series of periodontal conditions. The dental treatment of subjects that use illegal substances is becoming more common in the daily clinical practice of periodontists and other dental clinicians. When the clinicians encounter such patients, it is essential to manage their addiction properly taking into consideration the impact of it on comprehensive dental treatment. Further studies and clinical observations are required to obtain sound and definitive information.

Practical Considerations for the Use of Cannabis in Cancer Pain Management—What a Medical Oncologist Should Know

Pain is a highly debilitating emotional and sensory experience that significantly affects quality of life (QoL). Numerous chronic conditions, including cancer, are associated with chronic pain. In the setting of malignancy, pain can be a consequence of the tumor itself or of life-saving interventions, including surgery, chemotherapy, and radiotherapy. Despite significant pharmacological advances and awareness campaigns, pain remains undertreated in one-third of patients. To date, opioids have been the mainstay of cancer pain management. The problematic side effects and unsatisfactory pain relief of opioids have revived patients’ and physicians’ interest in finding new solutions, including cannabis and cannabinoids. The medical use of cannabis has been prohibited for decades, and it remains in Schedule 1 of the Misuse of Drugs Regulations. Currently, the legal context for its usage has become more permissive. Various preclinical and observational studies have aimed to prove that cannabinoids could be effective in cancer pain management. However, their clinical utility must be further supported by high-quality clinical trials.

Inhaled Marijuana and the Lung

Although vaping has recently increased as a mode of inhaling marijuana and has been associated with numerous and sometimes fatal cases of acute severe lung injury, smoking remains the most common method of inhaling marijuana and has been studied more extensively. Smoking marijuana has been shown to produce modest but significant short-term bronchodilation both in healthy subjects and those with asthma. Long-term effects of habitual marijuana smoking include the following: 1) symptoms of chronic bronchitis (increased cough, sputum production and wheezing); 2) modest effects on lung function in cross-sectional studies (no significant decrease in forced expired volume in 1 second [FEV₁) but mild reductions in FEV₁/forced vital capacity ratio [FEV₁/FVC], an increase in FVC and other lung volumes, reductions in specific airway conductance, and variable effects of maximal mid-expiratory flow rates and diffusing capacity; and 3) variable effects on age-related decline in FEV1 in longitudinal studies. Most cohort and case-control studies have failed to show that marijuana smoking is a significant risk-factor for lung cancer despite the presence of pro-carcinogenic components in marijuana smoke, although further study is warranted. The question whether marijuana smoking is associated with asthma is unclear and requires further investigation. Although delta-9 tetrahydrocannabinol (THC), the principal psychoactive component of marijuana, has immunomodulatory properties that hypothetically could increase the risk of pneumonia, the few available studies in marijuana smokers have failed to find an increased risk of pneumonia in immunocompetent users, although effects in immunosuppressed individuals have been variable.

Is There a Place for Medicinal Cannabis in Treating Patients with Sleep Disorders? What We Know so Far

The legalization of cannabis for medicinal, and in some countries, recreational, purposes in addition to growth in the cannabis industry has meant that cannabis use and interest in the area has increased rapidly over the past 20 years. Treatment of poor sleep and sleep disorders are two of the most common reasons for the current use of medicinal cannabis. However, evidence for the role of medical cannabis in the treatment of sleep disorders has not been clearly established, thus making it challenging for clinicians to make evidence-based decisions regarding efficacy and safety. This narrative review summarizes the highest quality clinical evidence currently available in relation to the use of medicinal cannabis for the treatment of sleep disorders including insomnia, obstructive sleep apnea, restless legs syndrome, rapid eye movement sleep behavior disorder, nightmare disorder and narcolepsy. A summary of the effect of cannabis on sleep quality and architecture is also presented. Currently, there is insufficient evidence to support the routine use of medicinal cannabis as an effective and safe treatment option for any sleep disorder. Nevertheless, emerging evidence is promising and warrants further investigation using standardized cannabinoid products and validated quantitative measurement techniques.

Wonder or evil?: Multifaceted health hazards and health benefits of Cannabis sativa and its phytochemicals

Cannabis sativa, widely known as 'Marijuana' poses a dilemma for being a blend of both good and bad medicinal effects. The historical use of Cannabis for both medicinal and recreational purposes suggests it to be a friendly plant. However, whether the misuse of Cannabis and the cannabinoids derived from it can hamper normal body physiology is a focus of ongoing research. On the one hand, there is enough evidence to suggest that misuse of marijuana can cause deleterious effects on various organs like the lungs, immune system, cardiovascular system, etc. and also influence fertility and cause teratogenic effects. However, on the other hand, marijuana has been found to offer a magical cure for anorexia, chronic pain, muscle spasticity, nausea, and disturbed sleep. Indeed, most recently, the United Nations has given its verdict in favour of Cannabis declaring it as a non-dangerous narcotic. This review provides insights into the various health effects of Cannabis and its specialized metabolites and indicates how wise steps can be taken to promote good use and prevent misuse of the metabolites derived from this plant.

Dabbing-Induced Hypersensitivity Pneumonitis

Dabbing has been gaining popularity among young people in recent years due to its ability to deliver a high concentration of tetrahydrocannabinol. When produced illegally, it is usually contaminated by toxic substances and associated with multiple health hazards. We present the case of a 66-year-old woman who developed hypersensitivity pneumonitis after dabbing butane hash oil for the first time and was successfully treated with corticosteroids with complete resolution of her symptoms. This case report emphasizes the respiratory complications associated with using a noxious substance like butane hash oil and gives physicians an insight into the diagnosis and management of dabbing-induced hypersensitivity pneumonitis.

Therapeutic Application of Cannabis in Medicine and Its Relevance to Thoracic Surgery

BACKGROUND

Cannabis is the most commonly used illicit substance in the United States. As cannabis use rises in popularity and its legalization continues to expand, the scientific community must address the controversy between beneficial and adverse effects of cannabis consumption.

METHODS

We performed a comprehensive literature review to study the medicinal and pathologic effects of cannabis use, with emphasis on its association with cancer pathophysiology and thoracic surgery.

RESULTS

We found evidence that cannabis products often contain carcinogenic materials and that their use is associated with the development of certain head and neck cancers, but not lung cancer. Indeed, several in vitro and in vivo studies have demonstrated that cannabis may have a therapeutic role in cancer given the antiproliferative effects of its active compounds such as δ-9-tetrahydrocannabinol. Cannabis-derived products have also been shown to be effective treatments for chronic pain, neuropathy, spasticity, and as antiemetics.

CONCLUSIONS

We acknowledge that additional studies are required to elucidate the long-term effects of cannabis products and that many potential biases and limitations exist in the literature due to self-reporting and limited survey studies. Appropriate stewardship over cannabis use among our patient population will likely determine its full implications in both oncologic and perioperative outcomes.

Alcohol and cannabis use alter pulmonary innate immunity

PURPOSE

Cannabis use is increasing due to recent legislative changes. In addition, cannabis is often used in conjunction with alcohol. The airway epithelium is the first line of defense against infectious microbes. Toll-like receptors (TLR) recognize airborne microbes and initiate the inflammatory cytokine response. The mechanism by which cannabis use in conjunction with alcohol affects pulmonary innate immunity mediated by TLRs is unknown.

METHODS

Samples and data from an existing cohort of individuals with alcohol use disorders (AUDs), along with samples from additional participants with cannabis use alone and with AUD were utilized. Subjects were categorized into the following groups: no alcohol use disorder (AUD) or cannabis use (control) (n = 46), AUD only (n = 29), cannabis use-only (n = 39), and AUD and cannabis use (n = 29). The participants underwent bronchoscopy with bronchoalveolar lavage (BAL) and airway epithelial brushings. We measured IL-6, IL-8, TNF⍺, and IL-10 levels in BAL fluid, and performed real-time PCR for TLR1-9 on the airway epithelial brushings.

RESULTS

We found significant increases in TLR2 with AUD alone, cannabis use alone, and cannabis use with AUD, compared to control. TLR5 was increased in cannabis users compared to control, TLR6 was increased in cannabis users and cannabis users with AUD compared to control, TLR7 was increased in cannabis users compared to control, and TLR9 was increased in cannabis users compared to control. In terms of cytokine production, IL-6 was increased in cannabis users compared to control. IL-8 and IL-10 were increased in AUD only.

CONCLUSIONS

AUD and cannabis use have complex effects on pulmonary innate immunity that promote airway inflammation.

"You're Ganja Have a Good Time": Investigating the Roots of Blunt Use Among a National Sample of Hispanic Adults

Blunt use is a pressing public health problem in the United States. While most studies have focused on African American youth, there remains a paucity of research examining blunt use among Hispanic individuals. Previous findings, which are quite limited, suggest mixed results, thus warranting further investigation regarding the prevalence of blunt use among Hispanic individuals and factors associated with such use. In accord with Jessor's problem behavior theory, we hypothesized that prior use of illicit substances and certain psychosocial risk factors pose an increased risk for blunt use among Hispanic adults. A secondary analysis examined prior substance use and psychosocial factors of 10,216 Hispanic lifetime blunt users participating in the 2017 National Survey on Drug Use and Health. Findings revealed that one in five (20.5%) Hispanic individuals reported lifetime blunt use. Significant risk factors associated with blunt use were age (18+ years or older), participation in a government assistance program, prior illicit substance use, and changes in appetite or weight. Additional research on other risk factors, prevention mechanisms, and treatment interventions for Hispanic individuals who use blunts is warranted.

Cannabis Associated "High" Cardiovascular Morbidity and Mortality: Marijuana Smoke Like Tobacco Smoke? A Déjà Vu/Déjà Vécu Story?

BACKGROUND

Cannabis use has increased over the past several years as some countries have legalized its use for the treatment of certain medical conditions and/or for recreational use. Thus, concerns have risen about potential adverse health effects. Increasing number of reports have associated cannabis use with serious cardiovascular (CV) complications. Furthermore, there appears to be a likeness in the harmful health effects, especially on the CV and respiratory systems, of cannabis smoking to those of tobacco smoking.

OBJECTIVE

To review the CV effects of cannabis use and compare them with those of tobacco use.

METHODS

Articles were reviewed that were published in English literature reporting on cannabis and cannabinoid pharmacology and their effects on the CV system and their consequences. Emphasis was also placed on articles reporting on cannabis use in adolescents, exposure to secondhand smoke, its effect on exercise and finally its inter-relationship and similarities with tobacco use.

RESULTS

With growing cannabis use, an increasing number of reports have emerged associating marijuana use with serious and life-threatening CV complications, including acute coronary syndromes, potentially lethal cardiac arrhythmias and ischemic strokes. There are certain similarities of the deleterious CV and respiratory effects of cannabis smoking with those of tobacco smoking. Despite the difference in the active ingredients (tetrahydrocannabinol vs. nicotine), each substance produces a plethora of chemicals when smoked and these are largely identical; furthermore, due to different modes of smoking, cannabis chemicals are retained in the body for a longer time. Of course, concomitant tobacco and cannabis smoking is a perplexing factor in isolating damages specifically pertaining to cannabis use, while the health risk is additive. Although the mechanisms producing CV harm may be somewhat different between these two substances, the outcome appears similar, or even worse, as the effects may emerge at a younger age.

CONCLUSION

There is an increasing concern that, apart from the mental health problem with cannabis smoking, societies may be facing another wave of a déjà vu/déjà vécu phenomenon similar to the tobacco smoking story.

Cannabis effects on brain structure, function, and cognition: considerations for medical uses of cannabis and its derivatives

Background: Cannabis is the most widely used illicit substance worldwide, and legalization for recreational and medical purposes has substantially increased its availability and use in the United States.Objectives: Decades of research have suggested that recreational cannabis use confers risk for cognitive impairment across various domains, and structural and functional differences in the brain have been linked to early and heavy cannabis use.Methods: With substantial evidence for the role of the endocannabinoid system in neural development and understanding that brain development continues into early adulthood, the rising use of cannabis in adolescents and young adults raises major concerns. Yet some formulations of cannabinoid compounds are FDA-approved for medical uses, including applications in children.Results: Potential effects on the trajectory of brain morphology and cognition, therefore, should be considered. The goal of this review is to update and consolidate relevant findings in order to inform attitudes and public policy regarding the recreational and medical use of cannabis and cannabinoid compounds.Conclusions: The findings point to considerations for age limits and guidelines for use.

Cannabis-Associated Asthma and Allergies

Inhalation of cannabis smoke is its most common use and the pulmonary complications of its use may be the single most common form of drug-induced pulmonary disease worldwide. However, the role of cannabis consumption in asthma patients and allergic clinical situations still remains controversial. To review the evidence of asthma and allergic diseases associated with the use of marijuana, we conducted a search of English, Spanish, and Portuguese medical using the search terms asthma, allergy, marijuana, marihuana, and cannabis. Entries made between January 1970 and March 2017 were retrieved. Several papers have shown the relationship between marijuana use and increase in asthma and other allergic diseases symptoms, as well as the increased frequency of medical visits. This narrative review emphasizes the importance to consider cannabis as a precipitating factor for acute asthma and allergic attacks in clinical practice. Although smoking of marijuana may cause respiratory symptoms, there is a need for more studies to elucidate many aspects in allergic asthma patients, especially considering the long-term use of the drug. These patients should avoid using marijuana and be oriented about individual health risks, possible dangers of second-hand smoke exposure, underage use, safe storage, and the over smoking of marijuana.

Integrative Approach to Pediatric Nausea

Nausea is a bothersome symptom that is commonly seen in the pediatric population. The pathophysiology of nausea is complex and involves the central nervous system, the enteric nervous system, gastrointestinal tract motility, and psychologic influences. Pharmacologic and nonpharmacologic therapies are available for treating nausea. Mind-body interventions (hypnosis, biofeedback), botanicals and supplements (ginger, enteric-coated peppermint oil), aromatherapy, and acupuncture have emerging evidence for effectively treating pediatric nausea. [Pediatr Ann. 2019;48(6):e236-e242.].

Marijuana medusa: The many pulmonary faces of marijuana inhalation in adolescent males

Marijuana use has risen dramatically over the past decade. Over this same time period, pediatric hospitals have seen an increase in presentation of adolescents with acute respiratory symptoms after recent marijuana inhalation. We report a case series of three adolescent males with significant findings of bilateral pulmonary nodules and ground glass opacities on chest imaging associated with recent marijuana inhalation. Lung biopsies in two of the three patients confirmed silica-induced pneumoconiosis. The third patient was diagnosed with acute hypersensitivity pneumonitis without lung biopsy. Improvement in clinical symptoms and lung function testing were noted in two of three patients after marijuana inhalation cessation. This case series highlights the variety of severe pulmonary presentations in adolescents following recent marijuana inhalation. Future studies are required to assess whether these presenting pulmonary complications are from direct marijuana exposure or indirect associations with marijuana inhalation injuries.

Medical Cannabis Use by Hodgkin Lymphoma Patients: Experience of a Single Center

Hodgkin lymphoma (HL) is one of the most curable malignancies. Despite its effectiveness, chemotherapy is often associated with adverse events (AEs) such as nausea, anorexia, and impairment of general well-being. Our objective was to assess the extent of medical cannabis use among HL patients and evaluate its efficacy in controlling chemotherapy-related AEs. Patterns of medical cannabis use and efficacy were evaluated using physician-completed application forms, medical files, and patient-completed questionnaires, for all consecutive adult HL patients treated at the Tel-Aviv Medical Center between June 2010 and November 2016. One-hundred and thirty-three patients met the inclusion criteria. The median age of the cohort was 37 years, 53% were male, 46% were diagnosed at an early stage, and 88% achieved a complete response to treatment. Fifty-one patients (38%) used medical cannabis. There were no significant differences in baseline characteristics between cannabis users and nonusers. Cannabis users reported improvement in pain, general well-being, appetite, and nausea in 94, 87, 82, and 79% of cases, respectively. Importantly, 81.5% reported a high overall efficacy of cannabis in relieving symptoms. AEs related to cannabis use itself were mild. Thus, medical cannabis use is prevalent in this HL cohort, and appears to be effective in ameliorating chemotherapy-related AEs.

The consequences of chronic cannabis smoking in vulnerable adolescents

Cannabis, like the mythic shape-shifter, presents in various guises, morphing with the perspective and context of the observer. Arguments about cannabis are confused by a myriad of debates-medical, social, ethical and political-as if a single conceptual umbrella can capture the variety and granularity of marijuana-related issues. This paper responds to marijuana use as it is commonly practised by youth in Australia. It has little to say about synthetic cannabinoids, specific medicinal cannabinoids, or medicinal properties of marijuana. We address those adolescents genetically and environmentally vulnerable to mental illness, with specific emphasis on indigenous and neurodevelopmentally impaired young people who show patterns of usage and response very different to adults and more resilient members of the population. Specifically, the practice of mixing tobacco with marijuana by aboriginal youth, and the resultant coalition of dependencies, will likely presage a rise in pulmonary and central nervous system pathology over the coming decades. Aboriginal youth begin using earlier, persist longer, and take greater quantities of cannabis than non-indigenous youth. This paper recommends practical interventions to reduce the multiple health consequences of chronic cannabis use in young people, especially indigenous young people.

Marijuana smoke induces severe pulmonary hyperresponsiveness, inflammation, and emphysema in a predictive mouse model not via CB1 receptor activation

Sporadic clinical reports suggested that marijuana smoking induces spontaneous pneumothorax, but no animal models were available to validate these observations and to study the underlying mechanisms. Therefore, we performed a systematic study in CD1 mice as a predictive animal model and assessed the pathophysiological alterations in response to 4-mo-long whole body marijuana smoke with integrative methodologies in comparison with tobacco smoke. Bronchial responsiveness was measured with unrestrained whole body plethysmography, cell profile in the bronchoalveolar lavage fluid with flow cytometry, myeloperoxidase activity with spectrophotometry, inflammatory cytokines with ELISA, and histopathological alterations with light microscopy. Daily marijuana inhalation evoked severe bronchial hyperreactivity after a week. Characteristic perivascular/peribronchial edema, atelectasis, apical emphysema, and neutrophil and macrophage infiltration developed after 1 mo of marijuana smoking; lymphocyte accumulation after 2 mo; macrophage-like giant cells, irregular or destroyed bronchial mucosa, goblet cell hyperplasia after 3 mo; and severe atelectasis, emphysema, obstructed or damaged bronchioles, and endothelial proliferation at 4 mo. Myeloperoxidase activity, inflammatory cell, and cytokine profile correlated with these changes. Airway hyperresponsiveness and inflammation were not altered in mice lacking the CB1 cannabinoid receptor. In comparison, tobacco smoke induced hyperresponsiveness after 2 mo and significantly later caused inflammatory cell infiltration/activation with only mild emphysema. We provide the first systematic and comparative experimental evidence that marijuana causes severe airway hyperresponsiveness, inflammation, tissue destruction, and emphysema, which are not mediated by the CB1 receptor.

Treating tobacco dependence: guidance for primary care on life-saving interventions. Position statement of the IPCRG

Tobacco smoking is the world's leading cause of premature death and disability. Global targets to reduce premature deaths by 25% by 2025 will require a substantial increase in the number of smokers making a quit attempt, and a significant improvement in the success rates of those attempts in low, middle and high income countries. In many countries the only place where the majority of smokers can access support to quit is primary care. There is strong evidence of cost-effective interventions in primary care yet many opportunities to put these into practice are missed. This paper revises the approach proposed by the International Primary Care Respiratory Group published in 2008 in this journal to reflect important new evidence and the global variation in primary-care experience and knowledge of smoking cessation. Specific for primary care, that advocates for a holistic, bio-psycho-social approach to most problems, the starting point is to approach tobacco dependence as an eminently treatable condition. We offer a hierarchy of interventions depending on time and available resources. We present an equitable approach to behavioural and drug interventions. This includes an update to the evidence on behaviour change, gender difference, comparative information on numbers needed to treat, drug safety and availability of drugs, including the relatively cheap drug cytisine, and a summary of new approaches such as harm reduction. This paper also extends the guidance on special populations such as people with long-term conditions including tuberculosis, human immunodeficiency virus, cardiovascular disease and respiratory disease, pregnant women, children and adolescents, and people with serious mental illness. We use expert clinical opinion where the research evidence is insufficient or inconclusive. The paper describes trends in the use of waterpipes and cannabis smoking and offers guidance to primary-care clinicians on what to do faced with uncertain evidence. Throughout, it recognises that clinical decisions should be tailored to the individual's circumstances and attitudes and be influenced by the availability and affordability of drugs and specialist services. Finally it argues that the role of the International Primary Care Respiratory Group is to improve the confidence as well as the competence of primary care and, therefore, makes recommendations about clinical education and evaluation. We also advocate for an update to the WHO Model List of Essential Medicines to optimise each primary-care intervention. This International Primary Care Respiratory Group statement has been endorsed by the Member Organisations of World Organization of Family Doctors Europe.

Medical Marijuana: Just the Beginning of a Long, Strange Trip?

Medical marijuana continues to gain acceptance and become legalized in many states. Various species of the marijuana plant have been cultivated, and this plant can contain up to 100 active compounds known as cannabinoids. Two cannabinoids seem the most clinically relevant: Δ9-tetrahydrocannabinol (THC), which tends to produce the psychotropic effects commonly associated with marijuana, and cannabidiol (CBD), which may produce therapeutic effects without appreciable psychoactive properties. Smoking marijuana, or ingesting extracts from the whole plant orally (in baked goods, teas, and so forth), introduces variable amounts of THC, CBD, and other minor cannabinoids into the systemic circulation, where they ultimately reach the central and peripheral nervous systems. Alternatively, products containing THC, CBD, or a combination of both compounds, can be ingested as oral tablets or via sprays applied to the oral mucosal membranes. These products may provide a more predictable method for delivering a known amount of specific cannabinoids into the body. Although there is still a need for randomized controlled trials, preliminary studies have suggested that medical marijuana and related cannabinoids may be beneficial in treating people with chronic pain, inflammation, spasticity, and other conditions seen commonly in physical therapist practice. Physical therapists, therefore, should be aware of the options that are available for patients considering medical marijuana and should be ready to provide information for these patients. Clinicians also should be aware that marijuana can produce untoward effects on cognition, coordination, balance, and cardiovascular and pulmonary function and should be vigilant for any problems that may arise if patients are using cannabinoids during physical rehabilitation.

[On the legalization debate of non-medical cannabis consumption : Position paper of the German Association for Psychiatry, Psychotherapy and Psychosomatics]

Calls are increasing for the legalization of cannabis. Some legal experts, various politicians, political parties and associations are demanding a change in drug policy. The legalization debate is lively and receiving wide coverage in the media. The German Association for Psychiatry, Psychotherapy and Psychosomatics (DGPPN) comments on the most important questions from a medical scientific perspective: can cannabis consumption trigger mental illnesses, what consequences would legalization have for the healthcare system and where is more research needed?

Effect of cannabis smoking on lung function and respiratory symptoms: a structured literature review

As cannabis use increases, physicians need to be familiar with the effects of both cannabis and tobacco on the lungs. However, there have been very few long-term studies of cannabis smoking, mostly due to legality issues and the confounding effects of tobacco. It was previously thought that cannabis and tobacco had similar long-term effects as both cause chronic bronchitis. However, recent large studies have shown that, instead of reducing forced expiratory volume in 1 s and forced vital capacity (FVC), marijuana smoking is associated with increased FVC. The cause of this is unclear, but acute bronchodilator and anti-inflammatory effects of cannabis may be relevant. Bullous lung disease, barotrauma and cannabis smoking have been recognised in case reports and small series. More work is needed to address the effects of cannabis on lung function, imaging and histological changes.

Damaging Effects of Cannabis Use on the Lungs

Cannabis is the most widely smoked illicit substance in the world. It can be smoked alone in its plant form, marijuana, but it can also be mixed with tobacco. The specific effects of smoking cannabis are difficult to assess accurately and to distinguish from the effects of tobacco; however its use may produce severe consequences. Cannabis smoke affects the lungs similarly to tobacco smoke, causing symptoms such as increased cough, sputum, and hyperinflation. It can also cause serious lung diseases with increasing years of use. Cannabis can weaken the immune system, leading to pneumonia. Smoking cannabis has been further linked with symptoms of chronic bronchitis. Heavy use of cannabis on its own can cause airway obstruction. Based on immuno-histopathological and epidemiological evidence, smoking cannabis poses a potential risk for developing lung cancer. At present, however, the association between smoking cannabis and the development of lung cancer is not decisive.