Puff, puff, pass

 

Since the arrival of e-cigarettes on the U.S. market in 2007, proponents of the vaping pen have heralded it as the modern answer to tobacco and an effective measure in reducing preventable disease. Just as quickly, they were dismissed by critics as wanting for evidence verifying its safety, often arguing that the wide range of flavours (ranging from the innocuous strawberries and cream to the bizarre hot dog) were formulated with a view towards attracting children and adolescents. In either case, the consensus in the medical community at present is that vaping is vastly preferable to traditional smoking.

However, less than 20% of smokers who try electronic cigarettes end up using them daily. In a study published in 2017, smokers attempting to make the switch complained that vaping “wasn’t quite there yet as a substitute” and didn’t produce “the same pleasure or effects” as tobacco. In online support groups, complaints abound from former tobacco users bemoaning the fact that vaping doesn’t eliminate their cravings. So, is there a tangible difference in the way vaping delivers nicotine?

The answer is a resounding “yes, probably” – though this depends on who you ask. Experts maintain that compared to cigarette smoking, vaping is simply an inferior nicotine delivery system. Indeed, one study showed that vaping in regular intervals for 5 minutes gave rise to a plasma concentration of nicotine only up to a third of that provided by one cigarette. But stranger answers come from other quarters. A minority in the vaping community argue that the reason vapes don’t satisfy tobacco smokers is that tobacco users aren’t addicted to nicotine at all. Instead, they prefer to use the term “tobacco addiction” and insist that nicotine alone is not an addictive substance.

While this seems a bizarre claim (nicotine withdrawal syndrome has been widely observed and well-defined), it does belie the widespread notion that nicotine addiction is perfectly well understood. The development of nicotine dependency has been shown to consist of a mix of reinforcement mechanisms, including primary drug reinforcement but also associative learning and pavlovian-style conditioning, which combine to give rise to a uniquely complex mechanism of dependency which continues to require research.

Nevertheless, it is true that other substances than nicotine in tobacco smoke potentiate nicotine dependency and increase the probability of relapse after cessation. Monoamine oxidase inhibitors such as norharman (found in active amounts in cigarette smoke) reduce the level of monoamine oxidase in smoker’s brains, and it has been shown in rats that inhibiting monoamine oxidase dramatically increased their motivation to self-administer nicotine. Other components like acetaldehyde have been shown to have addictive properties of their own.

While 95% of the alkaloids in tobacco consist of nicotine, 5% consists of different alkaloids which also have neuroactive effects. On the back of this, smokers on internet forums, disappointed with their vaping experience, have donned their pharmacological hats and pointed to this missing 5% as the source of their worries. Various e-liquid vendors have, in turn, released lines of Whole Tobacco Alkaloid (WTA) e-liquids, reportedly containing these missing molecules. Whether this 5% of alkaloids (which are already similar in structure to nicotine) are the culprits behind the smokers missing satisfaction, however, seems unlikely.

What seems more likely is that tobacco is intensely difficult to abstain from by design. One study published in the American Journal of Public Health found that 100 of 599 documented additives in cigarette tobacco had pharmacological effects of enhancing nicotine delivery and increasing the addictive potential of cigarettes. Ammonia added to cigarettes converts nicotine to its freebase form (the equivalent of converting cocaine to crack-cocaine), and researchers at Harvard University found that tobacco companies used additives to help ease smoking initiation in people who would otherwise find the smoke too harsh.

In any case, vaping remains for now a useful cessation aid, especially in combination with other therapies. And as the technology develops and long-term safety is ascertained, there continues to be hope that more and more smokers who want to make the change will be able to do so.