How is nicotine absorbed

Projection of the findings by Vansickel et al to our data is displayed in Figure 4. After 5 minutes of EC use, plasma nicotine levels were substantially lower compared to smoking one tobacco cigarette almost 3-fold lower compared to new- and 4-fold lower compared to first-generation device.

Plasma nicotine levels were equal between tobacco cigarette use at 5 minutes and new generation EC device at 35 minutes Data for tobacco cigarette was derived from Vansickel et al 7. Nicotine levels after smoking a tobacco cigarette in 5 minutes Additionally, plasma nicotine levels after smoking one tobacco cigarette are almost equal to the values after using the new-generation device for 35 minutes This is the first study that has compared the effect of using first- vs.

Experienced vapers were recruited, who use the EC devices more intensively compared to novice users 7. The results of the study showed that new-generation devices with high wattage output to the atomizer resulted in higher plasma nicotine levels compared to first-generation devices.

However, both devices delivered to the bloodstream far lower nicotine compared to a tobacco cigarette. ECs are the only nicotine delivery devices that resemble the motion and behavioral patterns of cigarette smoking.

Although the psycho-behavioral part of smoking is an important part of the overall addiction to smoking 16 , nicotine delivery still plays a major role. Smoking characteristically delivers significant amounts of nicotine to the blood stream at a fast rate This is probably the main reason for making it the most reinforcing and dependence-producing form of nicotine administration 17 , 18 , although recent data suggest that other substances in tobacco cigarette may reinforce the addictive properties of nicotine Studies have shown that the vast majority of EC users continue to use nicotine-containing liquids despite having quit smoking for several months 2 , 10 , Therefore, it seems that nicotine is important in ECs' success as smoking substitutes.

Despite that, the main findings herein showed that such a liquid is insufficient to deliver nicotine to the blood stream as rapidly as smoking. In fact, it took about 35 minutes of vaping with the new-generation device at high wattage in order to obtain plasma levels similar to smoking one cigarette in 5 minutes. The first-generation device was even less efficient in nicotine delivery; even 65 minutes of ad lib vaping was insufficient to deliver to the bloodstream nicotine at levels similar to smoking.

This was reflected in participants' answers to questionnaires, showing that satisfaction and craving reduction was higher after using the new- compared with the first-generation device. Moreover, better nicotine delivery may be the reason why new-generation devices are more popular in dedicated users, most of which have quit smoking by using ECs 10 , Possible reasons for these findings may be that nicotine delivered to the EC aerosol is not absorbed from the lungs but from the oral mucosa.

Therefore, nicotine absorption would be expected to occur at a similar rate to nicotine-replacement therapies NRTs. Moreover, a significant part of nicotine deposited to the oral mucosa is expected to be swallowed, with subsequent first-pass metabolism to the liver which reduces bio-availability Another possibility is that the vehicle of nicotine delivery liquid droplets of propylene glycol and glycerol may negatively interact with nicotine absorption from the lungs compared to the particulate matter, which is the delivery-vehicle of nicotine in smoking.

More studies are needed to define the reason for this lower rate of absorption from ECs. The new-generation device was more effective in this study because the higher amount of energy delivered to the atomizer results in higher amount of liquid aerosolized per puff, while first-generation devices deliver far lower energy and do not have an internal current stabilizer which maintains constant energy delivery until the battery is discharged.

Due to this, it is reasonable to expect that new-generation devices may be more effective as smoking substitutes compared to first-generation devices. Two randomised studies evaluating the efficacy of EC use in smoking cessation have used first-generation devices 22 , New-generation devices seem more promising because they deliver nicotine more effectively and this should be evaluated in future studies.

In any case, findings from this study indicate that ECs may also have less addictive properties and lower abuse liability, similar to what has been observed with NRTs 24 , due to the slow rate of nicotine absorption.

This has been specifically observed in a study by Vansickel et al Herein, participants reported lower dependence to ECs compared to smoking, however the retrospective nature of the answers for smoking could have biased the results. The decision was based on the level of liquid consumption from 5 minutes of use 6 , 7 , but did not take into consideration that consumption is different from absorption; the main factors associated with the effects of nicotine are the levels in the bloodstream and the speed of absorption.

Results of this study show that such nicotine concentration would be insufficient to deliver nicotine at levels similar to tobacco cigarettes unless ECs are used continuously for a long time.

Moreover, the incidence of nicotine overdose or intoxication from EC use can be virtually excluded. This could also result in reduced daily EC use and liquid consumption, since the amount of nicotine needed by each user could be obtained by reducing the time and intensity of EC use. Clinical studies should be performed assessing the efficacy and speed of nicotine delivery by using higher nicotine-containing liquids. There is a possibility that using higher nicotine-containing liquids may elevate the addictive potential of ECs; however, considering that there is currently minimal adoption of EC use by non-smokers adults and youngsters 11 , it is reasonable to expect that the current proposal will reduce the effectiveness of ECs in substituting smoking while no beneficial effect to other population groups will be observed.

Obviously, careful monitoring of use by these population groups is warranted; however, considering the current situation, a strict regulation banning the sales of ECs to minors would be more appropriate rather than adopting upper limits in nicotine content that would potentially reduce the efficacy of ECs to substitute smoking.

In conclusion, new-generation EC devices delivering higher energy to the atomizer seem to be more effective than first-generation devices in nicotine delivery to the user and in reducing cravings for nicotine.

It is reasonable to assume that nicotine levels in EC liquids should be considerably higher in order to improve their effectiveness in nicotine delivery, which is expected to make them more successful as smoking substitutes. Healthy experienced EC users vapers where recruited for this study. Exclusion criteria were: 1 pregnant or lactating females; 2 history of fainting or feeling faint associated with providing blood samples; and 3 being unwilling to provide written informed consent to participate to the study.

The protocol was approved by the ethics committee of our institution and written informed consent was signed by all subjects before participating to the study.

Two types of EC devices with the same liquid were used by the participants on two separate days, in a randomized cross-over design Figure 1. Users were provided with more fully-charged batteries if discharged and new cartomizers if emptied during the 65 minute period. The energy delivery to the atomizer was set to 9 watts. Carbon monoxide in exhaled breath was measured by a calibrated Bedfont Micro Smokerlyzer.

Participants were asked to take 10 puffs in 5 minutes, simulating tobacco cigarette use After this period, they were asked to use the ECs ad lib for 60 more minutes total duration of use: 65 minutes. Ten minutes after the end of the 65 minute period, carbon monoxide levels were measured again.

Blood samples were taken after the 5 minute period and every 15 minutes during the additional 60 minute period. The lowest limit of quantification LOQ for this method was 0. To evaluate their current EC dependence, the previously mentioned tests were also applied for EC use.

Since both questionnaires include a question for cigarette consumption, the question was adjusted for EC use based on the results of a survey of 19, EC users performed by our group unpublished data. The results of the two tests after excluding the question on cigarette and EC consumption were also reported. To avoid any interaction between the answers, the questionnaires for smoking and EC use were administered on separate days to the participants.

The sum of the scores from each question was calculated and reported. Participants were asked to draw a cross through the horizontal line and the score was calculated by measuring the distance between the cross and the left anchor. Both CWS and simple craving rating were asked at baseline, after 5 minutes and after 65 minutes of use.

Questions were adopted from Vansickel et al 8. The score was assessed in a similar way as described above for the simple craving rating. Categorical variables were expressed as number percentage while continuous variables as mean SEM. To compare CWS and simple nicotine craving scale, repeated measures analysis of variance ANOVA was used, with two within-subjects factors: timing 3 levels and session 2 levels.

To compare exhaled carbon monoxide levels, repeated measures ANOVA was also used but timing had 2 levels baseline and post minute ; for nicotine levels, timing had 6 levels.

To assess perceived effects of nicotine and EC use, paired student's t-test was used. All analyses were performed with commercially available statistical software SPSS v.

This is an officially non-profit association [ c 6 status by the IRS] that was founded and is run by electronic cigarette consumers. The study was investigator-initiated and investigator-driven.

The funding body had no involvement in the study design, data collection, analysis and interpretation, writing or approving the manuscript and decision to submit themanuscript for publication. Phillips, C. Debunking the claim that abstinence is usually healthier for smokers than switching to a low-risk alternative and other observations about anti-tobacco-harm-reduction arguments. Harm Reduct. Article Google Scholar. Farsalinos, K. Abuse 7, — Adkison, S. Electronic nicotine delivery systems: international tobacco control four-country survey.

One participant participant 4 who used a non-JUUL pod obtained the lowest nicotine boost Additionally, participant 5 had a greater baseline nicotine level and obtained a greater nicotine boost compared with other participants. Among experienced users who took 30 puffs in 10 minutes, the pod-based ENDS delivered a mean nicotine boost of This study is the first, to our knowledge, to show that JUUL delivers a higher and faster boost in blood nicotine than has been reported for most other ENDS devices.

However, its use produced a mean SD nicotine boost of Published: November 15, Corresponding Author: Jessica M.

Author Contributions: Dr Yingst had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Critical revision of the manuscript for important intellectual content: All authors. No other disclosures were reported. Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy Continue. Download PDF Comment. View Large Download. Participant and Device Characteristics. Tob Control. N Engl J Med. Development of a questionnaire for assessing dependence on electronic cigarettes among a large sample of ex-smoking e-cigarette users.

Nicotine Tob Res. Nicotine absorption during electronic cigarette use among regular users. PLoS One. Nicotine delivery, retention and pharmacokinetics from various electronic cigarettes.

Nicotine delivery to users from cigarettes and from different types of e-cigarettes. Psychopharmacology Berl. Get the latest research based on your areas of interest.

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