Introduction

Nicotine is a drug naturally found in tobacco leaves, which is commonly consumed for recreational use in forms such as cigarettes, cigars, e-cigarettes, vapes and patches.¹ The drug is classed as a powerful stimulant, meaning that it increases brain activity, making users have increased focus, alertness, and attention.² Other effects include increased heart rate and blood pressure, which with prolonged use, can increase the risk of heart disease and blood clot formation. The varied influence it has on chemicals in the brain (known as neurotransmitters) can affect the body physically and psychologically, making it incredibly addictive. 

Nicotine poisoning is when large amounts of nicotine are consumed in a short amount of time, causing an acute, sudden eruption of symptoms, including nausea, vomiting, tremors, seizures, high heart rate and blood pressure and, in some instances, coma.¹ With the increase in nicotine product availability, items such as e-cigarettes are easily accessed by children and adolescents, and there has been a rise in their use by this demographic in recent years.³ These products have nicotine concentrations intended for adult consumption; therefore, children and younger adolescents are more vulnerable to nicotine toxicity at smaller doses. Thus, parents and children need to be aware of the risks associated with nicotine consumption and the signs of toxicity. 

Sources of nicotine exposure in children

• First-hand smoke: Tobacco products such as cigarettes, chewing tobacco, and cigars⁴
• Second-hand smoke: Inhaled smoke from tobacco products that is being smoked by someone else, nicotine from the smoke can also be absorbed via skin and eye contact
• Third-hand smoke: Tobacco smoke can be absorbed by other surfaces and then absorbed by the child through contact, it is therefore advised that smoking parents and carers smoke outside of the home
• Modern nicotine products: E-cigarettes, vapes, lozenges, nicotine gum, and patches

Liquid nicotine found in e-cigarettes and vapes is highly concentrated and dangerous when consumed by children. These are usually inhaled by children and in some cases are accidentally ingested by or spilled on younger children.⁵

Infants can be exposed to nicotine before and after birth through second-hand smoke (usually from smoking parents) and if their mothers were consuming nicotine during pregnancy. Excessive nicotine exposure to infants has been linked to Sudden Infant Death Syndrome (SIDS) due to alterations in breathing patterns.⁶ There is evidence that nicotine-exposed infants are at risk of reduced breathing rates and have a reduced ability to adapt their breathing to certain environments, such as low oxygen and high carbon dioxide environments, which may be the mechanism to SIDS in such cases. 

How nicotine affects children?

When nicotine travels to the central nervous system, it binds to proteins known as nicotinic acetylcholine receptors (nAChR).⁷ The binding of nicotine to these proteins activates the release of dopamine, a neurotransmitter associated with the feeling of pleasure, which is a contributing factor to addiction. Prolonged exposure to nicotine results in desensitisation of nAChRs and alters dopamine release as well as other chemical pathways in the brain, which can ultimately contribute to increased nicotine intake and addiction, thus escalating the risk of nicotine poisoning.⁸   

nAChRs are also found in the peripheral nervous system, predominantly in muscles at the neuromuscular junction, where nerves and skeletal muscle meet. Although the exact effects nicotine has on the skeletal muscle are still poorly understood, there is evidence that at certain concentrations, it binds to nAChRs and reduces the release of the neurotransmitter acetylcholine, via multiple mechanisms.⁹ This ultimately suppresses the nerve signal travelling to the muscle and limits muscle’s ability to contract and move. Therefore, at high concentrations, children are at risk of severe, life-threatening symptoms such as respiratory arrest due to loss of control of the diaphragm and other respiratory muscles. 

Toxicity of nicotine

The popularity of e-cigarettes has greatly increased the risk of accidental ingestion of nicotine and poisoning in children, particularly those under the age of 5.¹⁰ These usually contain between 10 and 15 mg of nicotine, which when compared to the estimated toxic dose of 1.4mg per kg, is enough to cause poisoning in children weighing under 10kg. Therefore, younger and smaller children who are exposed to nicotine are at a higher risk of poisoning. 

Symptoms of nicotine poisoning

Early symptoms can arise in a matter of minutes of consumption and can last up to 24 hours.¹ Because nicotine acts on nAChRs in the central and peripheral nervous systems, there are different sets of symptoms associated with each system:⁵ 

• Central nervous system: Vomiting, dizziness, nausea, seizures, increased heart rate, and loss of muscle control and coordination (ataxia)
• Peripheral nervous system: Drooling, sweating, difficulty breathing, respiratory arrest, diarrhea

The severity and number of symptoms experienced usually correlate with the amount of nicotine consumed. Nicotine preferentially binds to nAChRs in the central nervous system, and does so quickly due to the easy crossing into brain tissue, making those symptoms more common and the first to arise. However, at high enough concentrations, the receptors in the peripheral nervous system become saturated and can block neuromuscular activity, preventing the movement of respiratory and other muscles.

Prevention strategies

Children who live with adults who use nicotine products need to be kept out of reach of these products at all times. E-cigarettes are often placed in easily accessible places and should be switched off and in out of reach places or locked away to prevent accidental contamination or consumption. Other sources of nicotine such as nicotine gum and patches should be stored in child-resistant packaging, like twist-down and turn caps, and zippered pouches.

Educating nicotine users about the risk of nicotine poisoning in children is important for spreading awareness and increasing caution around children. This includes understanding the common modes of absorption (such as skin, ingestion, and inhalation), that smaller doses can cause acute toxicity in children compared to adults, and the dangers associated with poisoning.

Management of nicotine poisoning 

If nicotine ingestion or contamination is suspected in your child, seek urgent care as soon as possible. Immediate action is to prevent any more nicotine absorption via decontamination.¹⁰ This usually involves the removal of clothes and rinsing the child’s skin with water. Usually, medical protocol for ingested toxic substances is to administer activated charcoal (to absorb the toxin and prevent absorption into the bloodstream via the gut) and either induce vomiting or remove stomach contents. However, in the case of nicotine poisoning, this is not recommended due to the risk of choking or aspiration, where the stomach contents enter the lungs. 

Due to the diversity of symptoms, children are monitored and treated based on their symptoms. For example, blood pressure, heart rate, oxygen saturation, and breathing rate are monitored closely. If a child begins seizing or has difficulty breathing, the airway is maintained in ways dependent on blood oxygen saturation. This can vary from oxygen administration, ventilation, and intubation (as a last resort).  

Summary

Nicotine poisoning in children is a medical emergency where a child consumes a large amount of nicotine in a short amount of time. Children can be exposed to nicotine from tobacco and artificial products like e-cigarettes, which can be absorbed through the skin, inhaled or ingested. The symptoms of nicotine poisoning include nausea, vomiting, dizziness, and difficulty breathing. You should seek urgent care if you think your child has been exposed to large amounts of nicotine and decontaminate your child if they have had nicotine spilled on them, but do not induce vomiting if you think they have ingested any. Prevention and awareness of how to reduce the likelihood of nicotine poisoning is vital to reduce chances of it ever occurring.