Nicotine is present in tobacco products such as cigarettes and hookahs as well as tobacco-free products like e-cigarettes. Although the euphoric effects of nicotine are more subtle than those of cocaine or heroin, nicotine is as addictive as these substances. The characteristic symptoms of nicotine addiction involve persisting with the use of nicotine-containing products despite being aware of their negative consequences on physical health.

Causes of Nicotine Addiction

Nicotine has pleasurable and reinforcing properties and causes adaptations in neurons in multiple brain areas, including dopamine neurons involved in response to rewarding stimuli. Adaptations or changes in dopamine neurons in the brain’s reward circuits make the continuous intake of nicotine necessary, and abstinence from nicotine results in withdrawal symptoms. The negative emotional state associated with the withdrawal symptoms often leads to relapse and results in the sustained use of nicotine products. Besides the intrinsic addictive properties of nicotine, various factors may also influence the risk of dependence.

  • Factors that influence dependence:

    • Genetics: The presence of certain variants of genes, including those for the receptors to which nicotine binds (nicotine acetylcholine receptor), can increase the likelihood of developing a dependence on nicotine
    • Age of onset: The chances of developing a dependence on nicotine are higher if individuals start using nicotine-containing products at an early age.
    • Social environment: The use of nicotine-containing products by family and friends is associated with a higher likelihood of individuals using cigarettes or other nicotine-containing products
    • Co-occurring mental health disorders: Individuals suffering from depression, anxiety, schizophrenia and other such psychiatric disorders are more likely to develop a dependence on nicotine
    • Use of other substances: Higher rates of smoking are observed in individuals who use alcohol, marijuana and other illicit substances

Nicotine Addiction Symptoms

Nicotine is considered to be as addictive as heroin or cocaine. Addiction to nicotine is characterized by an inability to control nicotine use despite adverse physical effects. Physical symptoms include physical dependence and withdrawal symptoms upon abstinence. Psychological symptoms of nicotine dependence include forming associations between nicotine use and various environmental cues. These cues include people, places and habits and tend to trigger nicotine use.

  • Physical Symptoms

    Some of the physical symptoms of nicotine addiction include:

    • Trouble quitting nicotine use despite persistent efforts to do so
    • Development of physical dependence on nicotine characterized by an inability to function without using nicotine
    • Development of tolerance and need for larger doses of nicotine to achieve the desired effect
    • Smoking, vaping or chewing tobacco despite negative effects on physical health
    • Development of withdrawal symptoms involving depressed mood, anxiety, irritability, insomnia, restlessness or fatigue upon abstinence
    • Activities revolving around whether one can or cannot smoke, vape or chew

  • Psychological Symptoms:

    Besides developing a physical dependence on nicotine, individuals may also become psychologically dependent on nicotine. Some of the psychological symptoms of nicotine addiction may include:

    • Believing that one needs to use nicotine to function normally
    • Formation of associations between nicotine use and social or other daily activities. Such associations may also be formed between nicotine use and places or people. The formation of such associations results in these activities or other cues acting as triggers for nicotine use. For example, needing a cigarette or other nicotine-containing product along with a cup of coffee or other activities like after eating a meal
    • Withdrawal symptoms such as irritability, restlessness, anger and anxiety upon abstinence

Signs of Nicotine Addiction

Some of the visible signs of nicotine addiction may depend on the method of intake. Some of the recognizable symptoms of nicotine dependence include increased heart rate and blood pressure, weight loss, increased arousal.

  • Some of the signs of smoking may include:

    • Staining of teeth
    • Persistent cough
    • Hoarseness
    • Frequent colds or respiratory infections
    • Bad breath
    • Clothes and hair smelling of smoke
    • Fingers and fingernails may be stained yellow
    • Frequent breaks or excuses to smoke
    • Time to first cigarette and number of cigarettes per day tend to be reliable indicators of addiction

  • Some of the signs of vaping or using e-cigarettes may include:

    • Bloodshot eyes
    • Persistent cough
    • Sweet smell due to flavors used in the e-liquid
    • Increased thirst
    • Nosebleeds

Side Effects of Nicotine Addiction

Long-term use of nicotine can lead to physical and psychological dependence on the substance. Some of the effects of nicotine addiction or long-term use can include:

  • Increased heart rate
  • Hypertension (high blood pressure)
  • Cardiac arrhythmias
  • Cardiac arrest
  • May increase the risk of coronary artery disease and type-2 diabetes

Additionally, nicotine intake during adolescence can interfere with normal brain development and have lasting effects on cognitive functioning. Chronic nicotine intake during adolescence can lead to lasting deficits in memory and attention and impaired impulse control. Prolonged nicotine use can also interfere with brain development, resulting in increased susceptibility to mood disorders like depression and anxiety, and dependence on other illicit substances like methamphetamine and cocaine.

Nicotine Replacement Therapy

Nicotine replacement therapy is one of the most common methods to help individuals abstain from smoking or using other tobacco-containing products. Nicotine replacement therapy involves the use of low doses of nicotine to decrease cravings for tobacco products and reduce the intensity of withdrawal symptoms. Some of the products used include nicotine patches, nicotine gum or lozenges. These therapeutic aids do not contain many of the toxic chemicals present in tobacco smoke or the adulterants present in e-liquids.

Products such as nicotine gum and lozenges are meant to be used only for three months unless prescribed for a longer duration by a physician. However, since these products also contain nicotine, some individuals (less than 10%) tend to develop a dependence on them and continue using them for many years.

These products have much lower nicotine levels than cigarettes and do not contain toxic chemicals that cause cancer, but addiction to nicotine lozenges or nicotine gum may increase the risk of cardiovascular conditions with long-term use. In cases of prolonged use and addiction to nicotine gum or lozenges, withdrawal symptoms involving depression, anxiety, irritability and anxiety may emerge upon discontinuation of the use of these products. Hence, a physician may switch such individuals to a different nicotine-containing product like a nasal spray or nicotine patches and gradually taper the dose of nicotine.

  • Nicotine Lozenge Addiction Side Effects:

    Some of the potential side effects caused by the use of nicotine lozenges include:

    • Nausea
    • Hiccups
    • Heartburn
    • Coughing
    • Headaches
    • Insomnia

  • Nicotine Gum Addiction Side Effects:

    Some of the side effects of nicotine gum include:

    • Increased heart rate
    • Nausea
    • Vomiting
    • Cough
    • Indigestion
    • Irritability
    • Mouth sores and blisters
    • Increased production of saliva

Can You Overdose on Nicotine?

It is possible to overdose on nicotine if nicotine gum or lozenges are used simultaneously with cigarettes. The use of e-cigarettes has also increased the possibility of an overdose due to the lack of regulations regarding the composition of the e-liquid used in the cartridges. Accidentally consuming even a small amount (1 teaspoon) of the liquid can be lethal and there have been several cases of nicotine poisoning due to children inadvertently consuming the e-liquid.

  • Some of the signs of nicotine poisoning may include:

    • Nausea
    • Diarrhea
    • Vomiting
    • Confusion
    • Involuntary muscle twitches
    • Seizures
    • Arrhythmias (abnormal heart rate)
    • Breathing disturbances
    • Respiratory failure
    • Death

Help for Nicotine Addiction

Quitting the use of nicotine-containing products can be difficult, and both behavioral and pharmacological approaches can help individuals overcome their nicotine addiction. Behavioral treatments including cognitive behavioral therapy and motivational enhancement therapy are effective in helping individuals quit nicotine use. Cognitive-behavioral therapy involves teaching individuals to recognize thoughts and behaviors that lead to the use of nicotine products and teaching them coping skills to avoid nicotine use. Motivational enhancement therapy involves counseling to increase the individual’s motivation to quit smoking (or use of other nicotine-containing products).

Besides face-to-face counseling, telephone counseling and web-based services can also be effective in helping individuals quit nicotine products. In instances of addiction to tobacco products, nicotine replacement therapy may help individuals to stop using these products. Nicotine replacement therapy involves the use of products that contain lower doses of nicotine, and these products help to alleviate the withdrawal symptoms and reduce cravings. Other medications like bupropion and varenicline can also help reduce cravings and aid the cessation of nicotine intake. These pharmacotherapies are more effective when combined with behavioral approaches.