Nicotine is a substance found in all tobacco products and some e-cigarette liquids. It is a highly addictive substance that is naturally present in the tobacco plant. Laboratories can also produce nicotine synthetically.

People also use the substance as an insecticide in the agricultural industry.

Any product containing tobacco also contains nicotine. This includes cigarettes, heated tobacco products, cigars, and most e-cigarettes.

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Nicotine comes from the Nicotiana species, which are tobacco plants and part of the nightshade family. Tobacco plants originated in South America before spreading to North America, Africa, and Australia.

Native people of these areas originally used the leaves of tobacco plants to chew, smoke, or use in religious rituals. European colonists exported tobacco crops for profit and changed the focus of tobacco to recreational use.

The tobacco industry has a substantial history of using racial profiling, demographics of an area, and cultural factors to target particular communities and promote tobacco use.

Tobacco companies have also disproportionately marketed menthol products to Black people and low-income communities. Tobacco companies add menthol to cigarettes to make them more palatable.

According to the Centers for Disease Control and Prevention (CDC), among people who smoke cigarettes, non-Hispanic Black or African American people are more likely to smoke menthol cigarettes compared to other races or ethnicities.

Menthol may increase the addictive effects that nicotine has on the brain. People who smoke menthol cigarettes are more likely to continue using tobacco products, which increases the risk of them developing conditions relating to tobacco use.

According to the National Institute on Drug Abuse (NIDA), nicotine creates a temporary feeling of well-being and relaxation, and increases heart rate and the amount of oxygen the heart uses. As nicotine enters the body, it causes a surge of endorphins, which are chemicals that help to relieve stress and pain and improve mood.

The body quickly absorbs nicotine into the bloodstream so it can reach the brain. Nicotine levels peak quickly after entering the body, so the feelings of reward are short-lived. This can create a cycle of people continuing to smoke to keep feeling the pleasurable sensations.

Nicotine also increases levels of dopamine, a neurotransmitter that is part of the brain’s reward system and creates feelings of pleasure and reward. The release of dopamine reinforces a person’s behavior of taking nicotine.

Frequent use of nicotine creates changes in the way the brain works in relation to self-control, stress, and learning. Long-term changes can lead to addiction and withdrawal symptoms when a person is not smoking.

Effects on cognitive function

Nicotine may also temporarily improve concentration and memory. However, long-term smoking of cigarettes may link to a decline in cognitive ability and an increased risk of Alzheimer’s disease. Therefore, any short-term benefits on cognitive function do not outweigh the long-term risks from nicotine use.

When people stop using nicotine, they may experience withdrawal symptoms affecting their attention or memory. Withdrawal from severe nicotine use may also result in sleep impairment.

Nicotine can affect various systems throughout the body, including:

Side effect
Central nervous systemdizziness and lightheadedness
• sleep disturbances
• changes in blood flow
Cardiovascular system• increased risk of blood clotting
• increased blood pressure
• changes in heart rhythm and rate
Respiratory systemshortness of breath
• bronchospasms
• increased risk of conditions such as chronic obstructive pulmonary disease
Muscular systemtremors
joint pain
Gastrointestinal systempeptic ulcer
dry mouth
indigestion or heartburn

Certain nicotine products may also have specific side effects. According to the American Cancer Society, side effects of nicotine patches include:

A racing heartbeat may mean the dose of nicotine is too high, and people can talk with a healthcare professional about lowering the dosage.

Side effects of nicotine gum may include:

Other nicotine products may also cause a racing heartbeat, nervousness, and headaches. If a person thinks they are experiencing nicotine poisoning, they need to contact Poison Control or seek emergency medical help.

Nicotine may interact with some other drugs or medications. Nicotine may cause benzodiazepines to be less effective. If a person is taking a contraceptive pill, nicotine may increase the risk of blood clots forming.

Learn more about types of drug interactions here.

Nicotine is addictive and the main psychoactive substance in tobacco, which means it alters how the brain works. According to the NIDA, most people who smoke use tobacco regularly due to nicotine addiction.

Smoking is the most common preventable cause of death in the United States. It causes damage to almost every organ in the body and increases the risk of severe health problems, including heart disease, stroke, and lung cancer.

Nicotine does not cause cancer, but tobacco smoke contains at least 69 carcinogenic (cancer-causing) chemicals.

Are e-cigarettes and vaporizers safe?

Researchers still do not know the safety and long-term health effects of using e-cigarettes and other vaping products. In September 2019, federal and state health authorities began investigating an outbreak of a severe lung disease associated with e-cigarettes and other vaping products. We are closely monitoring the situation and will update our content as soon as more information is available.

Electronic nicotine delivery systems, which people may refer to as e-cigarettes or vaporizers, are small, portable devices that heat a liquid into vapor. The liquid usually contains nicotine, along with solvents and flavorings.

There are currently a lot of unknowns about vaping, including the chemicals they may contain and the effect they have on health.

A 2021 animal study on e-cigarette use suggested a negative impact on memory and learning after 4 and 12 weeks of e-cigarette exposure.

Additionally, the Food and Drug Administration (FDA) has issued a report on the potential dangers of using vaping products containing tetrahydrocannabinol (THC), a component of cannabis.

The FDA also warns against using any vaping product from an unknown source or bought off the street. There have been over 1,000 reports of serious lung injuries as a result of using vaping products.

If people are using e-cigarettes to help them quit smoking, other methods may be a better option.

Nicotine is a highly addictive substance. Nicotine dependence refers to the psychological and physical factors that make it challenging to stop using products containing nicotine.

According to NIDA, a 2020 survey found that around 23.6 million people ages 12 and older had nicotine dependence in the previous 30 days.

Nicotine affects the chemistry of the brain and central nervous system. When a person uses nicotine, it causes temporary feelings of relaxation and well-being. It increases levels of dopamine and provides a small adrenaline rush.

As these effects wear off, a person may begin to feel feelings of irritation and anxiety, causing them to consume more nicotine.

As this cycle continues, a person will begin to experience withdrawal symptoms. Additionally, the body adapts to nicotine, meaning more is needed to experience the same effects.

Learn more about nicotine dependence.

Treatment for nicotine dependency may include:

Nicotine replacement therapy

Nicotine replacement therapy (NRT) provides people with a small amount of nicotine that attaches to some of the body’s nicotine receptors to reduce nicotine cravings.

NRT may include nicotine patches, sprays, lozenges, or gum. FDA-approved NRTs are the least harmful types of nicotine products.


Certain medications may also help treat nicotine dependence.

Bupropion is a medication that affects brain chemicals and is as effective as NRT in helping people quit.

Varenicline is a medication that stimulates a specific nicotine receptor but to a lesser extent than nicotine. It may be more effective than bupropion in helping people quit.

There is also a prescription-only nicotine inhaler. Instead of being inhaled into the lungs, the nicotine is mostly absorbed into the back of the throat.

Counseling and psychological support

People may choose to speak with a mental health professional for advice or use psychotherapy such as cognitive behavioral therapy (CBT). Mindfulness, helplines, automated text messages, and self-help materials may also help people to quit.

The National Cancer Institute also has a smoking quitline. It offers counseling, resources, and support for those who wish to quit smoking.

Nicotine is a highly addictive substance found in tobacco products and can be the reason many people consume tobacco. It may cause side effects such as dizziness, racing heartbeat, and headaches.

It is also a toxic substance that can cause poisoning. If people suspect they have nicotine poisoning, they will require immediate medical help.

Nicotine may also cause people to use tobacco products such as cigarettes more often, which can cause severe health problems.

Medications, nicotine replacement therapies, and behavioral treatment can help people to stop using products that contain nicotine.

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