Introduction

Vaping was introduced in 2007 and has grown exponentially in popularity since then.¹ It is a modern nicotine delivery method where the individual inhales vapour containing nicotine along with other chemicals, including flavouring and liquid carriers such as propylene glycol or glycerol. It was initially introduced to steer people away from the conventional cigarette as they were thought to be a healthier alternative.² Vaping works by the individual inhaling vapour from a device called an e-cigarette, and it is designed to mimic the smoking action users do with cigarettes.

Though e-cigarettes were introduced as a healthier alternative to smoking, there is a big concern for nicotine overdose. The concentration of nicotine within e-liquid is increasing, which has further heightened this concern. From 2017 to 2022, the e-liquid capacity in disposable e-cigarettes has increased by 518%, and the nicotine strength has risen by 294% from 1.7% to 5%. A study conducted in 2019–2020 found that 27 people died from e-cigarette/vaping-associated lung injuries,  highlighting the concern healthcare providers have for users of these products.³

What is Nicotine and Why is it Dangerous?

Nicotine is an organic chemical compound and highly addictive stimulant which is naturally found in tobacco plants; however, it is also found in other vegetation, such as tomatoes or potatoes, in smaller quantities. A common reason for nicotine consumption is the fact that, in low dosages, nicotine can help people concentrate and reduce feelings of stress. Almost immediately after the nicotine is inhaled, it is absorbed into the bloodstream. This triggers a chemical reaction which stimulates the release of dopamine (a chemical associated with pleasure and reward). For this reason, it is addictive, as it induces a mood-altering and pleasurable feeling toward the individual,  helping them feel more focused.⁴

Despite this feeling many individuals experience, depending on the dosage and duration of exposure to nicotine, it can have significant adverse effects on the body. In terms of what is happening chemically and biologically,  nicotine binds to molecules in the brain called acetylcholine receptors, and this can increase brain activity. It can increase the risk of psychiatric disorders such as depression or bipolar disorder.

One major consequence of nicotine consumption is the effect it has on the cardiovascular system by increasing blood pressure, increasing heart rate, and narrowing your arteries.⁵ The combined effect of these can strongly lead to the individual developing heart disease or having a heart attack.⁶

Other adverse effects (long- and short-term) of excessive nicotine use include:

• Decreased appetite
• Diarrhoea
• Gastrointestinal distress
• Nausea
• Premature ageing
• Sweating
• Lung disease/cancer

Excessive intake of nicotine can cause nicotine poisoning/overdose. According to the National Institute for Occupational Safety and Health, the lethal dose of inhaled nicotine is 50–60 mg/kg in the average male.⁷

How Vaping Increases Overdose Risk

Before the introduction of e-cigarettes, cases of nicotine poisoning were relatively rare. However, in more recent years, due to the high concentration of nicotine within e-cigarettes, it has become more common, raising widespread concern. Vapour can be inhaled more deeply in comparison to smoke from cigarettes, so the effects of nicotine are accelerated. As a result of this, users slowly become desensitised to low concentrations of nicotine, leading them to resort to the higher concentrations of nicotine that the e-cigarette industry has tailored to.

To meet this growing demand, many e-cigarette industry leaders started to develop nicotine salts, which are the chemically modified form of e-cigarette liquid. It is more alkaline and has been designed to improve user comfort when used, as it reduces throat burning and undue bitterness. This makes higher nicotine consumption more palatable for users, which is a troubling development.⁸

With the rapid escalation of nicotine strength and development of stronger formulations, users (particularly the youth) may accidentally vape too fast and causing unwanted side effects.

Symptoms of Nicotine Overdose

Nicotine poisoning can affect individuals of all ages; however, generally speaking, those who have lower body weights, such as small adults or children, have a heightened response to nicotine. The symptoms of nicotine overdose can vary between individuals. It is usually a biphasic progression.

First phase symptoms may include:

• Nausea and vomiting
• Hypersalivation
• Pain in the abdominal region
• Pale skin
• Excess sweating
• Increase of blood pressure
• Hyperpnoea (heavy breathing)
• Loss of balance
• Difficulty walking
• Tremors
• Headaches
• Dizziness
• Extreme fatigue

As the overdose progresses to the second phase, symptoms become more severe and may include:

• Diarrhoea
• Low blood pressure
• Slow heart rate
• Abnormal heart rhythms
• Shock
• Coma
• Paralysis
• Muscle weakness
• Difficulty breathing / respiratory failure
• Cardiac arrest

Nicotine overdose may lead to death, which can be a result of paralysis of the muscles that are responsible for breathing, build-up of fluids in the airways, or heart failure.

Groups at Higher Risk

The colourful packaging and variety of sweet flavours offered by many e-cigarettes appeal more to the youth, making them a high-risk group for nicotine overdose. With the growing nicotine concentration and the development of new ways to consume nicotine, such as salts, this demographic is more vulnerable to this risk.⁹ In fact, a study conducted in 2022 found that 16–24-year-olds were more likely to report daily vaping amongst all other age groups.¹⁰

A risk is posed to those who use e-cigarettes to help them stop smoking completely. However, as the nicotine concentration within the e-cigarette industry is rapidly increasing, this may cause misuse with e-liquid—for example, using a strong concentration by mistake. This can inadvertently lead to a higher dependency on nicotine, further fuelling their addiction and therefore increasing their risk of overdose.

Nicotine can be easily exposed to children in many ways. In the case of e-cigarettes, they may mistakenly consume liquid nicotine solutions. As aforementioned, small height and weight make the effects of nicotine much more severe and potentially life-threatening to children.¹¹ Accidental swallowing is very common in toddlers and accounts for an average of 2 in every 100 emergency hospital cases.¹²

Regulation and Product Labelling

Some countries regulate the nicotine concentration within e-cigarettes and do not permit over a certain concentration to be sold. For safe use of e-cigarettes, packaging should be completely transparent about everything about the product. However, a study conducted within the UK found that 76.5% of suppliers didn’t state that nicotine is addictive, 13% had no ingredients listed, and there was inconsistent and unclear reporting of nicotine levels. This vagueness within the packaging can lead to misuse of e-cigarettes or other nicotine forms. For this reason, clear labels and warnings are vital when launching products into the market.¹³

Prevention and Safe Practices

Even though there are lots of valid concerns surrounding vaping, e-cigarettes can still serve their intended purpose, which is to help people quit smoking. Local stop smoking services can aid individuals in selecting e-liquids with enough liquid to reduce withdrawal symptoms and reduce cravings to gradually help individuals quit overall. When doing this, it is vital to monitor how often and how much you vape so that you can track and progressively decrease nicotine concentration.

When purchasing vapes, it is important to do so through a well-established, professional company like a specialist vape shop, pharmacy, or supermarket. These establishments are regulated to ensure product safety and quality, including adherence to legal limits on nicotine concentration.¹⁴

For the safety of small children or pets, it is important that if you are an e-cigarette user or use anything that supplies nicotine, they are stored away and out of reach from children or pets to avoid the risk of them accidentally consuming them.

Summary

To summarise, vaping is a modern nicotine delivery method and was originally introduced to steer people away from conventional cigarettes and ultimately quit smoking. Though it can still be used for its original purpose, in recent years, healthcare professionals have been extremely concerned about nicotine overdose associated with vaping. With the growing concentrations of nicotine found within e-cigarettes, along with newly developed formulations such as nicotine salts designed to help high nicotine concentrations become more palatable to the user, these have contributed to a noticeable increase in nicotine adverse side effects.
Nicotine overdose presents a wide variety of symptoms with varying severity. In extreme cases, it can be fatal. For this reason, it is important that individuals are well-educated about the risks associated with vaping and progressively reduce nicotine consumption to protect their health and well-being.