What to Know About Nicotine Use

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Nicotine, a stimulant found in tobacco plants, is one of the most heavily used drugs in the U.S.—and it's just as addictive as cocaine or heroin, according to the U.S. surgeon general.

Cigarette smoking is the primary source of nicotine, with one pack of cigarettes providing some 250 "hits" of the extremely addictive substance.

Fewer people over the age of 18 are smoking today than ever before, but it still remains the most preventable cause of death in the United States. It accounts for 480,000 deaths annually. Estimates from the Centers for Disease Control and Prevention for 2017 indicate that 14 percent of the U.S. adult population smoke cigarettes.

Common Nicotine Products: cigarettes, pipes, cigars, chewing tobacco, snuff, hookahs, e-cigarettes, vapes

Drug Class: stimulant

Common Side Effects: decreased appetite, heightened mood, increased heart rate and blood pressure, nausea, diarrhea, better memory, increased alertness

What Does Nicotine Do?

When a person inhales cigarette smoke, the nicotine in the smoke is rapidly absorbed into the blood and starts affecting the brain within 10 seconds. Once there, nicotine triggers a number of chemical reactions that create temporary feelings of pleasure for the smoker, but these sensations are short-lived, subsiding within minutes.

This includes the release of adrenaline, the "fight or flight" hormone. Physically, adrenaline increases a person's heart rate, blood pressure and restricts blood flow to the heart muscle. When this occurs, smokers experience rapid, shallow breathing and the feeling of a racing heartbeat. Adrenaline also tells the body to dump excess glucose into the bloodstream.

Nicotine also inhibits the release of insulin from the pancreas, a hormone that is responsible for removing excess sugar from a person's blood. This leaves the smoker in a slightly hyperglycemic condition, meaning he or she has more sugar in the blood than is normal.

High blood sugar acts as an appetite suppressant, which may be why smokers experience that cigarettes reduce the feeling of hunger.

As the nicotine level drops in the blood, smokers feel edgy and agitated—the start of nicotine withdrawal. In order to relieve this discomfort, smokers light up another cigarette... and then another... and another.

Nicotine addiction is a vicious cycle. One cigarette is never enough—a fact that every smoker knows all too well.

What the Experts Say

Many researchers are beginning to question whether nicotine is any more harmful than a daily dose of caffeine. To date, there have been studies showing positive effects of nicotine, including decreased tension and increased thinking, as well as the stimulants potential in warding off cognitive decline into Alzheimer's, delaying the progression of Parkinson's disease, and as a therapeutic approach for ADHD and schizophrenia.

Still, health professionals continue to warn about the dangers of nicotine, especially when used by adolescents whose brains are still developing (until age 25).

Nicotine impacts the parts of the brain that play a role in attention, memory, learning, and brain plasticity.

While cigarette smoking is on the decline, vaping is on the rise. The American Academy of Pediatrics warns, “e-cigarettes are threatening to addict a new generation to nicotine,” and recommends increasing the minimum age to purchase e-cigarettes to 21 nationwide. 

Off-Label or Recently Approved Uses

Nicotine replacement therapy (NRT) was the first pharmacological treatment approved by the Food and Drug Administration (FDA) for smoking cessation. In fact, studies show that using the nicotine patch can double the rate of a person's smoking cessation success, especially when combined with support.

There are a variety of available NRT products, including:

  • Nicotine patch
  • Nicotine gum
  • Nicotine nasal spray
  • Nicotine inhaler
  • Nicotine lozenges

Common Side Effects

Nicotine causes a range of effects on both the body and mind, including:

  • Decreased appetite
  • Heightened mood
  • Increased activity in the intestines
  • Increased production of saliva and phlegm
  • Increased heart rate
  • Increased blood pressure
  • Sweating
  • Nausea
  • Diarrhea
  • Better memory
  • Increased alertness

Signs of Use

If your loved one is smoking cigarettes, you’ll likely be able to smell it on him or her. Detecting vaping can be a bit more difficult—but there are still some signs of use:

  • Devices: E-cigarettes can look like thumb drives, pens, or like a stylus, with holes on each end.
  • Irritability: This is a classic sign of withdrawal.
  • Sweet smells: Vapor juice is often flavored, so if you suddenly catch a whiff of fruit punch or bubble gum (and there’s no candy around) it could be a red flag.
  • Nosebleeds: Vaping can dry out the nasal passages and cause nose bleeds.
  • Drinking more liquids: The vaporized liquid in e-cigs contains propylene glycol, which attracts and holds water molecules from the mouth, causing constant dry mouth.

Can You Overdose on Nicotine?

Nicotine is poisonous and overdose is possible, though not common. Most often, nicotine poisoning occurs when children mistake nicotine gum or lozenges for candy.

If you or someone you care about experiences the following signs of nicotine overdose, call 911 or poison control (800-222-1222) immediately:

  • Difficulty breathing
  • Vomiting
  • Fainting
  • Headache
  • Weakness
  • Increased or decreased heart rate

Myths and Common Questions

Many people think that nicotine causes cancer—but the jury is still out. Nicotine is certainly a harmful, addictive substance but it is mainly the tar as well as the other toxic chemicals in cigarette smoke that causes cancer.

Research does suggest that nicotine can increase the risk of cancer due to its damaging effects on DNA, although the risk is much lower than those from smoking cigarettes. A study by the National Cancer Institute found that those who were most addicted to nicotine—smoking a cigarette within five minutes of waking up—had the greatest risk of developing lung cancer.

Another myth is that you can get hooked on the nicotine in smoking cessation products like the patch or nicotine gum or lozenges. While possible, most people find it easy to get off nicotine medicine after several months. In general, these products deliver nicotine to your body slower. 

Many teens think that using e-cigarettes is safer, however, they still contain high levels of nicotine. The brand JUUL packs perhaps the most potent dose: one pod contains roughly 20 cigarettes worth of nicotine and the product claims to deliver the addictive substance nearly three times faster than other e-cigarettes.

Tolerance, Dependence, and Withdrawal

Nicotine is extremely addictive and, when you use it regularly, your body and mind learn to expect a certain amount of nicotine each day—and if it doesn't get it, withdrawal can be intense. You can build a tolerance to nicotine, needing more to reach the desired effect. This is one reason why it's so hard (but not impossible) to quit smoking.

How Long Does Nicotine Stay in Your System

Nicotine (in the form of a cigarette, pipe, or e-cigarette) is mostly absorbed into the body through the lungs as well as the membranes in the mouth and throat. It can also be absorbed in your gastrointestinal tract (via chewing tobacco, nicotine gum, lozenges) or your skin if you use a nicotine patch.

Nicotine is mainly metabolized in the liver and is excreted via urine through the kidneys as well as in feces. How long it stays in your system depends on many factors, including age, weight, type, frequency of use, and hydration and physical activity levels.

That said, the estimated timeframe is as follows:

  • Urine test: two to four days
  • Blood test: two to four days
  • Saliva test: one to four days
  • Hair follicle test: up to 90 days

Many routine drug tests screen for nicotine.


Smokers are often surprised to learn that they are addicted to a substance. Many people believe that smoking is just a bad habit; something they could stop easily when they decided it was time.

Nicotine is a highly addictive substance that's found in all tobacco products, including cigarettes, pipes, cigars, chewing tobacco, snuff, hookahs, e-cigarettes, and other vaping devices.

Nicotine activates the same reward pathways in the brain that other drugs of abuse such as cocaine or amphetamines do, although to a lesser degree. Research has shown that nicotine increases the level of dopamine in the brain, a neurotransmitter that is responsible for feelings of pleasure and well-being.


The acute effects of nicotine wear off within minutes, so smokers must continue dosing themselves frequently throughout the day to maintain the pleasurable effects of nicotine and to prevent nicotine withdrawal, which causes a host of physical and psychological symptoms:

  • Cravings to smoke
  • Irritability, crankiness
  • Insomnia
  • Fatigue
  • Inability to concentrate
  • Headache
  • Cough
  • Sore throat
  • Constipation, gas, stomach pain
  • Dry mouth
  • Sore tongue and/or gums
  • Postnasal drip
  • Tightness in the chest

How to Get Help

Statistics show that only a small percentage (approximately 7 percent) of people who try to quit smoking without support are still smoke-free a year later. However, those with a quit program in place that includes education about nicotine addiction and a solid support group, do much better.

Whether you prefer to quit cold turkey or choose to use a quit aid to help you stop smoking, realize this: Recovery from nicotine addiction is a process of gradual release over time.

It doesn't happen overnight, but with perseverance, freedom from nicotine addiction is doable and will pay you back with benefits that go well beyond what you can probably imagine.

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Article Sources

  • Centers for Disease Control and Prevention. Smoking and Tobacco Use. https://www.cdc.gov/tobacco/data_statistics/index.htm.

  • Mishra, A., ChaturvediIndian, P., et al. "Harmful Effects of Nicotine." Indian Journal of Medical Paediatric Oncology. 2015 Jan-Mar; 36(1): 24–31. DOI: 10.4103/0971-5851.151771.

  • Truth Initiative. "How Much Nicotine Is in Juul?" https://truthinitiative.org/research-resources/emerging-tobacco-products/how-much-nicotine-juul.