E-cigarettes come in many different shapes and sizes. Earlier models often resembled traditional cigarettes and had a limited appeal for youth [11]. The first surge in popularity among teens occurred between 2013-2015 with the proliferation of pen-like and larger, complex devices made available in a wide range of youth-friendly flavours [12]. A second rapid increase in popularity was between 2017-2019 with the arrival of small, pod-based devices using pre-filled cartridges [13]. Fig. 1 presents a schematic representation of various e-cigarette devices [14].

Reproduced with permission from the Centers for Disease Control and Prevention, USA [14]. Fig. 1 E-cigarettes and other vaping devices.

The amount of nicotine contained in most e-liquids varies between 15 and 50 mg/mL. E-cigarettes exposes adolescents to nicotine toxicity and potential nicotine overdose [15] as they can absorb high amounts of nicotine in a short time period [16,17]. For example, a typical 2mL e-cigarette pod at 5% concentration would contain 100 mg of nicotine which could be consumed in as little as one hour with uninterrupted use [17,18]. The lethal dose of nicotine has been said to be between 30 and 60 mg for adults, but may be much higher [19].

Use of nicotine during adolescence is associated with altered brain development and long-term impairments in memory, attention capacity and executive functioning [20-23]. Consuming large amounts of nicotine through aping can lead to nicotine toxicity, which presents with headaches, abdominal pain, nausea, vomiting, heart palpitations, hand tremors, difficulty concentrating, and in some cases, seizures and cardiac arrhythmia. Nicotine is also a long-term risk factor for poor cardiovascular health [ 24-26].

Regular nicotine use through vaping can also lead to withdrawal symptoms if adolescents try to quit or are temporarily unable to access vaping products. Withdrawal symptoms can appear after as little as a few weeks of use and can interfere with normal daily functioning [27-29].

Acute injuries like facial and limb burns due to malfunction of vaping devices have also been described [30]. Additionally, vaping aerosols include carcinogenic and irritating substances that may lead to chronic respiratory symptoms such as cough, bronchitis, asthma exacerbation and decreased exercise tolerance [31,32].

More than 2,800 cases of severe e-cigarette or vaping-associated lung injury (EVALI) were reported in Canada and the US in 2019 and early 2020, of which approximately 15% cases were reported in youth under the age of 18 years [33]. EVALI consists of a sterile inflammatory pneumonitis that presents with cough, chest pain, and shortness of breath, which can be severe and lead to hospitalization and even death [33]. While no cases have been reported in India, and much remains unknown about this condition, it is suspected that vitamin E acetate (found in several cannabis-containing e-liquids) may lead to such presentations [33].

Pediatricians should ask adolescent patients if they have tried vaping, if they currently vape, and discuss vaping-associated health risks with all adolescents. The discussion should include commercial brand names for more clarity and details should be asked about products and substances used, motives, context, frequency, intensity and motivations to quit if applicable [34,35]. Using standardized scales for nicotine dependence (such as the Hooked on Nicotine Checklist) or diagnostic criteria for cannabis use disorder according to the Diagnostic and Statistical Manual of Mental Disorders (DSM–5) can also be useful to understand the severity of the vaping habit and addiction to nicotine and/or cannabis.

Ask, Advise, Assess, Assist, and Arrange–initially developed for smoking cessation, can also be a helpful framework for an effective vaping counseling intervention [35,36]. After asking about vaping, pediatricians should advise all adolescents not to initiate or to quit vaping and discuss one or two of the health risks associated with vaping (e.g. EVALI). Pediatricians can then assess the young person’s motivation to quit or cut down, for instance, by using a 10-point scale (i.e. "on a scale from 1 to 10, how motivated are you to quit/cut down on vaping?"). Based on the response, the pediatrician can then offer to assist the adolescent with vaping cessation. Finally, pediatricians should arrange a follow-up plan, involving families and/or other health care providers when applicable.

As there are no evidence-based pharmaceutical treatments tested specifically for adolescents with vaping addiction, the first line of treatment for vaping cessation relies on behavioral strategies. Strategies that have proven effective for tobacco dependence should be considered including individual or group counseling, motivational inter-viewing, cognitive-behavioral therapy, contingency management, mindfulness-based interventions, as well as smartphone and web-based strategies [34,35].

Considering that most vaping liquids contain nicotine, often in high amounts, nicotine replacement therapy such as patches, gums and lozenge can be used safely with adolescents in addition to behavioral strategies [34]. The use of anti-craving medications such as bupropion and varenicline can also be considered alone or in addition to nicotine replacement [34].

A recent Cochrane review suggests that among adults, e-cigarettes used alone or in combination with other pharmaceuticals or behavioral methods may be of similar effectiveness for smoking cessation as approved nicotine replacement products [36]. People who oppose the recent ban on e-cigarettes in India, support that e-cigarettes are a valuable tool for Tobacco Harm Reduction (THR) as an aid for adult smokers hoping to quit smoking. A meta-analysis of 299 articles established that newer generations of e-cigarettes may serve as an efficient means of meeting the nicotine demand of a person addicted to smoking, with significantly reduced health consequences compared to conventional cigarettes [37].

However, whether this adult data can be extrapolated to youth remains unknown [36]. The evidence for pharmacotherapy for youth e-cigarette cessation remains extremely limited. Adolescents, with a still-developing pre-frontal cortex, are more vulnerable to the addictive properties of nicotine, which may impact the level to which adult data can be extrapolated.

Although, e-cigarette use may cause youth to transit to combustible tobacco products, it could also increase adult cessation of combustible tobacco cigarettes. The net public health effect, harm or benefit, of e-cigarettes depends on three factors: i) Effect on youth initiation of combustible tobacco products, ii) Effect on adult cessation of combustible tobacco products, and iii) Intrinsic toxicity. E-cigarette use by adult smokers needs to lead to long-term abstinence from combustible tobacco cigarettes to lead to considerable benefit to public health. Without that, e-cigarette use could cause considerable harm due to the inherent harms of exposure to e-cigarette toxicants and to the harms related to potential subsequent combustible tobacco use by those who begin using e-cigarettes in their youth [11].

Some of the most serious concerns have been expressed by school principals in Delhi regarding the increasing trend of youth vaping among young students [43]. The sale of vaping devices has spiraled upward since their introduction in the Indian market in 2007 to the point that many schools have become surrounded by vape shops [43]. In September 2019, India became one of the first countries to enact a complete ban on all e-cigarette products. This ban followed an intense period of discussion and debate weighing the advantages and potential disadvantages of such a ban [44], and the publication of a white paper from the Indian Council of Medical Research a few months prior [45].

Acknowledgment: Dr. Samir Shah for help with referencing and table creation

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