What Is Nicotine?

Commonly Used Recreational Drug

Nicotine is an addictive organic compound found in tobacco plants. It’s the chemical that makes smoking cigarettes, chewing tobacco, and vaping so hard to quit.

Nicotine is associated with many health risks and problems. Tobacco is linked to cancer of the mouth, throat, and lungs. Smoking cigarettes causes emphysema and chronic obstructive pulmonary disease (COPD).

Quitting smoking or chewing tobacco can lead to nicotine withdrawal symptoms. Nicotine replacement therapy like gum, lozenges, and patches are used to help people quit smoking, chewing, and vaping.

This article discusses nicotine, how it is used, and the risks associated with tobacco. It also explains how nicotine replacement therapy can help you to quit smoking and chewing tobacco.

Nicotine illustration
Malachy120 / iStock / Getty Images

What It Is

Nicotine is a plant alkaloid, which means that it's a naturally occurring chemical that contains nitrogen. It's also a highly addictive stimulant. Nicotine is most popularly known for its use in cigarettes and tobacco products, but it has some other uses.

Although nicotine is predominantly found in tobacco plants, it’s also present in tomatoes, eggplants, potatoes, and green pepper plants. And while they all belong to the nightshade family, the quantities of nicotine in these other plants are much lower than in tobacco plants. 

How Nicotine Works

There are certain proteins in our bodies referred to as receptors. These receptors only receive specific neurotransmitters or chemicals. The receptors that nicotine binds to are called nicotinic-cholinergic receptors. Nicotine is an agonist, which means that when it binds to receptors, it brings about a biological response.

Nicotinic-cholinergic receptors are found in many places in the body, including the brain, neuromuscular junctions (areas of chemical communication between nerves and muscles), the inner part of the adrenal gland, and ganglia (groups of nerve cells).

Nicotine‘s stimulating abilities come from the fact that when it binds to receptors, neurotransmitters (messenger chemicals) like dopamine, acetylcholine, beta-endorphin, norepinephrine, serotonin, and ACTH are released in the body.

Some of these neurotransmitters—like dopamine, beta-endorphin, and serotonin—regulate pleasure, mood, emotion, and pain relief. The dopamine release, for instance, is what causes one to feel pleasure after smoking a cigarette. 

Other neurotransmitters like acetylcholine control physiological responses like heart contractions and muscle movements. This is why a person’s heart rate might speed up, arteries constrict, or their blood pressure becomes elevated right after nicotine is consumed.


Nicotine has uses as a recreational drug, a treatment for addiction tobacco, and as a pesticide.


Nicotine is used as a recreational drug because of its mood-altering and pleasure-inducing effects. Nicotine use is very prevalent. Nearly 40 million adults in the U.S smoke cigarettes. 

Yet while cigarettes are the most common medium through which nicotine is consumed recreationally, there are other nicotine products like e-cigarettes, chewing tobacco, cigars, snuff, and pipe tobacco.

Continuous use of nicotine leads to long-term changes in the brain. The repeated dopamine release from nicotine consumption teaches the brain to keep using nicotine, and this leads to addiction.

Nicotine use and addiction can cause many illnesses, disabilities, and even death. Over 8 million people die worldwide every year as a direct result of tobacco use. Overcoming nicotine addiction is difficult. Only about 6% of smokers are successfully able to quit every year.

As of Dec. 20, 2019, the new legal age limit is 21 years old for purchasing cigarettes, cigars, or any other tobacco products (including hookah tobacco) in the U.S.


Nicotine is used to help treat addiction to or dependence on smoking cigarettes. Quitting smoking abruptly can cause one to experience many severe effects and cravings called withdrawal symptoms. Products that deliver low doses of nicotine are sometimes used to ease quitting and manage withdrawal symptoms.

This form of treatment is called nicotine replacement therapy (NRT). NRT products contain less nicotine than cigarettes and do not contain many harmful chemicals typically found in cigarettes. 

Nicotine replacement can come in the form of patches, gum, lozenges, inhalers, and nasal sprays. Heavy smokers may be medically directed to use a combination of NRT products. When used consistently, NRT increases a person's chances of successfully smoking by 50% to 70%.


In the natural environment, nicotine protects tobacco plants from herbivores. Nicotine has been used as an insecticide for centuries, although its use this way has seriously dwindled.

In 2014, the Environmental Protection Agency banned nicotine pesticides from being sold commercially in the United States. Nicotine pesticides are also banned in countries under the European Union. 

Instead, chemicals called neonicotinoids are used in many pesticide products. Neonicotinoids are derived from nicotine and are chemically similar to nicotine. Aside from plant protection, they are also used for tick and flea control for pets. 

In 2018, the European Commission banned the outdoor use of neonicotinoids pesticide due to public health concerns and potential threats to bees. In the U.S., many pesticides containing neonicotinoids have been banned, and some restrictions apply to the use of others still permitted for the same reasons as the European ban.


Nicotine and tobacco products are legal for sale to adults over the age of 21 in the United States. Prior to December 2019, the minimum age of sale of tobacco products in the U.S was 18. While laws and age restrictions vary, nicotine and tobacco products are legal in most other countries in the world.


There are many health risks and side effects associated with using nicotine.
Some of the health risks include:

  • Nicotine contributes to the development of emphysema—a type of chronic obstructive pulmonary disease— in smokers.
  • It’s potentially carcinogenic. Chronic nicotine use is linked to lung, gastrointestinal, pancreatic, and breast cancer.
  • Nicotine use is associated with peptic ulcer disease (PUD) and gastroesophageal reflux disease (GERD). 
  • Nicotine use increases the risk of hypertension and cardiovascular diseases.
  • Nicotine use during pregnancy increases the likelihood of complications and adverse outcomes like miscarriages and stillbirth.
  • Children exposed to nicotine in the womb are more predisposed to health problems throughout their lifetimes. These health problems affect their endocrine, reproductive, neurologic, respiratory, and cardiovascular systems.
  • Nicotine use can cause cardiac arrhythmia—a cardiovascular condition characterized by an irregular heartbeat.

Some of the side effects of nicotine use are:

  • Stomach pain
  • Diarrhea
  • Nausea
  • Vomiting
  • Headaches
  • Back pain
  • Dizziness
  • Increased heart rate
  • Nervousness

Potential Benefits

Although conclusive research is still unavailable, nicotine may have some health benefits when taken long-term. These benefits include protection against illnesses and diseases like:

Nicotine may also help with weight loss.

A Word From Verywell

Nicotine is a highly addictive substance, and it’s advisable to avoid using it recreationally. If you’re trying to quit smoking and plan to use nicotine replacement therapy to ease the process, you should speak to your healthcare provider first. 

Frequently Asked Questions

  • What are the signs of nicotine withdrawal?

    Common nicotine withdrawal symptoms include: 

    • Anxiety 
    • Cravings or urges to smoke, chew, or vape
    • Depression
    • Difficulty concentrating
    • Increased appetite 
    • Insomnia
    • Irritability 
    • Moodiness
    • Restlessness
    • Weight gain
  • Does nicotine affect mental health?

    Nicotine has a reputation for relieving anxiety. Nicotine dependence is more common among people with ADHD, anxiety disorders, and depression. Research suggests nicotine may play a role in relieving symptoms of these mental illnesses. 

    At the same time, nicotine withdrawal can cause anxiety, depression, and difficulty concentrating. The science isn’t clear on why people with mental health issues are more likely to use tobacco. It could be because it relieves symptoms or because withdrawal symptoms compound the underlying issues, making it harder to quit.

  • How long does nicotine stay in your system?

    Nicotine byproducts can be detected in urine for up to four days. The test measures levels of cotinine, a nicotine metabolite. Cotinine levels are generally:

    • Less than 10 nanograms per milliliter (ng/mL) in nonsmokers
    • Between 11 ng/mL and 30 ng/mL in light smokers or those exposed to secondhand smoke
    • Higher than 500 mg/mL in heavy smokers 
  • Is nicotine replacement therapy safe?

    Yes, nicotine replacement therapy (NRT) is safe to use. NRT does not cause death or disease as tobacco products do. The dangers of smoking and chewing tobacco is associated with chemicals other than nicotine. There is no evidence that NRT can cause health problems.

    Potential side effects of NRT include a rash from the nicotine patch or upset stomach, heartburn, and indigestion from nicotine gum or lozenges. 

16 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Data and statistics: Smoking & tobacco use.

  2. National Institute on Drug Abuse for Teens. Why is nicotine so addictive?.

  3. World Health Organization. Tobacco.

  4. National Institute on Drug Abuse. Is nicotine addictive?.

  5. Federal Register. Nicotine; Product cancellation order.

  6. European Commission. Neonicotinoids.

  7. U.S. Environmental Protection Agency. EPA releases proposed interim decisions for neonicotinoids.

  8. U.S. Food and Drug Administration. Selling tobacco products in retail stores.

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  11. Harvard Health. Nicotine: It may have a good side.

  12. Barreto GE, Iarkov A, Moran VE. Beneficial effects of nicotine, cotinine and its metabolites as potential agents for Parkinson's diseaseFront Aging Neurosci. 2015;6:340. doi:10.3389/fnagi.2014.00340

  13. Lakhan SE, Kirchgessner A. Anti-inflammatory effects of nicotine in obesity and ulcerative colitisJ Transl Med. 2011;9,129. doi:10.1186/1479-5876-9-129

  14. Centers for Disease Control And Prevention. Tips from former smokers: 7 common withdrawal symptoms and what you can do about them.

  15. Kutlu MG, Parikh V, Gould TJ. Nicotine addiction and psychiatric disorders. Int Rev Neurobiol. 2015;124:171-208. doi:10.1016/bs.irn.2015.08.004

  16. University of Rochester Medical Center. Nicotine cotinine (urine).

Additional Reading
  • Chaturvedi P, Mishra A, Datta S, Sinukumar S, Joshi P, Garg A. Harmful effects of nicotineIndian Journal of Medical and Paediatric Oncology. 2015;36(1):24. doi:10.4103/0971-5851.151771

  • PubChem. Nicotine.

By Tolu Ajiboye
Tolu Ajiboye is a health writer who works with medical, wellness, biotech, and other healthcare technology companies.