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Concept: Vaporizer


Inhalable, noncombustible cannabis products are playing a central role in the expansion of the medical and recreational use of cannabis. In particular, the practice of “dabbing” with butane hash oil has emerged with great popularity in states that have legalized cannabis. Despite their growing popularity, the degradation product profiles of these new products have not been extensively investigated. The study herein focuses on the chemistry of myrcene and other common terpenes found in cannabis extracts. Methacrolein, benzene, and several other products of concern to human health were formed under the conditions that simulated real-world dabbing. The terpene degradation products observed are consistent with those reported in the atmospheric chemistry literature.

Concepts: Medicine, Health, Cannabis, Hashish, Recreational drug use, Vaporizer, Hemp oil, Hash oil


Increased medical and legal cannabis intake is accompanied by greater use of cannabis vaporization and more cases of driving under the influence of cannabis. Although simultaneous Δ(9)-tetrahydrocannabinol (THC) and alcohol use is frequent, potential pharmacokinetic interactions are poorly understood. Here we studied blood and plasma vaporized cannabinoid disposition, with and without simultaneous oral low-dose alcohol.

Concepts: Cannabinoid receptor, Cannabis, Cannabinoid, Cannabidiol, Cannabinoids, Vaporizer, Raphael Mechoulam


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.

Concepts: Pulmonology, Asthma, Respiratory physiology, Chronic obstructive pulmonary disease, Tetrahydrocannabinol, Cannabis, Spirometry, Vaporizer


Therapeutic cannabis administration is increasingly used in Western countries due to its positive role in several pathologies. Dronabinol or tetrahydrocannabinol (THC) pills, ethanolic cannabis tinctures, oromucosal sprays or table vaporizing devices are available but other cannabinoids forms can be used. Inspired by the illegal practice of dabbing of butane hashish oil (BHO), cannabinoids from cannabis were extracted with butane gas, and the resulting concentrate (BHO) was atomized with specific vaporizing devices. The efficiency of “cannavaping,” defined as the “vaping” of liquid refills for e-cigarettes enriched with cannabinoids, including BHO, was studied as an alternative route of administration for therapeutic cannabinoids. The results showed that illegal cannavaping would be subjected to marginal development due to the poor solubility of BHO in commercial liquid refills (especially those with high glycerin content). This prevents the manufacture of liquid refills with high BHO concentrations adopted by most recreational users of cannabis to feel the psychoactive effects more rapidly and extensively. Conversely, “therapeutic cannavaping” could be an efficient route for cannabinoids administration because less concentrated cannabinoids-enriched liquid refills are required. However, the electronic device marketed for therapeutic cannavaping should be carefully designed to minimize potential overheating and contaminant generation.

Concepts: Tetrahydrocannabinol, Cannabis, Psychoactive drug, Cannabidiol, Hashish, Recreational drug use, Vaporizer


Objective To understand whether the impact of smoking on chronic rhinosinusitis (CRS) is reversible after smoking cessation. Study Design Cross-sectional study. Setting Academic tertiary care rhinology clinic. Subjects and Methods A total of 103 former-smoker CRS patients and 103 nonsmoker CRS patients were prospectively recruited. The primary outcome measure was sinonasal symptom severity measured with the 22-item Sinonasal Outcomes Test (SNOT-22), and secondary outcome measures were general health-related quality of life (QOL) measured with the 5-dimensional EuroQol visual analog scale (EQ-5D VAS) and patient-reported CRS-related antibiotic and oral corticosteroid usage in the past year. Outcome measures were compared between cohorts and checked for association with time since cessation of smoking for former smokers. Results Compared with nonsmokers, former smokers had worse SNOT-22 score ( P = .019) and EQ-5D VAS score ( P = .001) and reported using more CRS-related antibiotics ( P = .003) and oral corticosteroids in the past year ( P = .013). In former smokers, every year was associated with a statistically significant improvement in SNOT-22 score (β = -0.48; 95% CI, -0.91 to -0.05; P = .032), EQ-5D VAS score (β = 0.46; 95% CI, 0.02-0.91; P = .046), and CRS-related oral corticosteroid use (relative risk = 0.95; 95% CI, 0.91-0.98; P = .001). Given the differences in our study outcome measures between former smokers and nonsmokers, we estimate that the reversible impacts of smoking on CRS may resolve after 10 to 20 years. Conclusions CRS patients who are former smokers have worse sinonasal symptomatology, QOL, and CRS-related medication usage than nonsmokers. Every year since cessation of smoking is associated improvements in sinonasal symptomatology, QOL, and CRS-related oral corticosteroid use, potentially reaching nonsmoker levels after 10 to 20 years.

Concepts: Antibiotic resistance, Smoking, Tobacco, Passive smoking, Nicotine, Smoking cessation, Corticosteroid, Vaporizer


BACKGROUND: Cannabis is the most prevalent illicit drug identified in impaired drivers. The effects of cannabis on driving continue to be debated, making prosecution and legislation difficult. Historically, delays in sample collection, evaluating the inactive Δ(9)-tetrahydrocannabinol (THC) metabolite 11-nor-9-carboxy-THC, and polydrug use have complicated epidemiologic evaluations of driver impairment after cannabis use.Content:We review and evaluate the current literature on cannabis' effects on driving, highlighting the epidemiologic and experimental data. Epidemiologic data show that the risk of involvement in a motor vehicle accident (MVA) increases approximately 2-fold after cannabis smoking. The adjusted risk of driver culpability also increases substantially, particularly with increased blood THC concentrations. Studies that have used urine as the biological matrix have not shown an association between cannabis and crash risk. Experimental data show that drivers attempt to compensate by driving more slowly after smoking cannabis, but control deteriorates with increasing task complexity. Cannabis smoking increases lane weaving and impaired cognitive function. Critical-tracking tests, reaction times, divided-attention tasks, and lane-position variability all show cannabis-induced impairment. Despite purported tolerance in frequent smokers, complex tasks still show impairment. Combining cannabis with alcohol enhances impairment, especially lane weaving.Summary:Differences in study designs frequently account for inconsistencies in results between studies. Participant-selection bias and confounding factors attenuate ostensible cannabis effects, but the association with MVA often retains significance. Evidence suggests recent smoking and/or blood THC concentrations 2-5 ng/mL are associated with substantial driving impairment, particularly in occasional smokers. Future cannabis-and-driving research should emphasize challenging tasks, such as divided attention, and include occasional and chronic daily cannabis smokers.

Concepts: Epidemiology, Cannabinoid receptor, Tetrahydrocannabinol, Cannabis, Cannabis smoking, Hashish, Crash, Vaporizer


Cannabis (marijuana) smoke and tobacco smoke contain many of the same potent carcinogens, but a critical-yet unresolved-medical and public-health issue is whether cannabis smoking might facilitate the development of lung cancer. The current study aimed to assess the risk of lung cancer among young marijuana users.

Concepts: Epidemiology, Cancer, Lung cancer, Smoking, Tobacco, Tobacco smoking, Smoke, Vaporizer


Cannabis use has increased in the United States, particularly the use of vaporized cannabis oil, which is often mixed with thinning agents for use in vaporizing devices. E-cigarette research shows that heated thinning agents produce potentially harmful carbonyls; however, similar studies have not been conducted (1) with agents that are commonly used in the cannabis industry and (2) at temperatures that are appropriate for cannabis oil vaporization. The goal of this study was to determine whether thinning agents used in the cannabis industry produce potentially harmful carbonyls when heated to a temperature that is appropriate for cannabis oil vaporization.

Concepts: United States, Heat, Carbonyl, Liquid, Evaporation, Vaporizer, Vaporization, Carbonyl sulfide


A new method for administering cannabinoids, called butane hash oil (“dabs”), is gaining popularity among marijuana users. Despite press reports that suggest that “dabbing” is riskier than smoking flower cannabis, no data address whether dabs users experience more problems from use than those who prefer flower cannabis.

Concepts: Cannabis, Cannabinoid, Hashish, Vaporizer, Cannabis sativa, Hemp oil, Hash oil


Pre-clinical studies link cannabinoid-1 receptor activation to inflammation and atherosclerotic effects; anti-inflammation and immunosuppression seem to be mediated by cannabinoid-2 receptor activation. In this epidemiological study, we aim to present estimates on suspected cannabis-attributable immunomodulation as manifest in serum C-reactive protein (CRP) levels as non-specific inflammatory markers with interpretable clinical values. With strength of data from recent large nationally representative community sample surveys, the research approach illustrates value of a quantile regressions approach in lieu of the commonly used but relatively arbitrary cutpoints for CRP values.

Concepts: Immune system, Inflammation, Epidemiology, Smoking, Value, C-reactive protein, Acute-phase protein, Vaporizer