What Is Nicotine?

Nicotine is a chemical found in the tobacco plant and is the primary reason people develop an addiction to smoking, chewing tobacco, and vaping.

While most forms of ingesting nicotine deliver similar amounts, some e-cigarette brands are known to have higher nicotine levels. An adult who ingests 60 milligrams or a child who ingests 10 milligrams at once is at risk for adverse effects.

The Environmental Protection Agency lists nicotine as an “acute hazardous waste.”

Nicotine is a light yellow or brown liquid, though exposing it to air or light will turn it brown. When warm, it can have a fish-like odor. When hot, it emits toxic fumes, like carbon monoxide and nitrogen oxides.

Nicotine is absorbed in the lungs, skin, and buccal mucous membranes and then enters the bloodstream. When ingested, the liver metabolizes most of the nicotine, where enzymes break it down into cotinine. What is not broken down by liver enzymes is eliminated by the kidneys in a person’s urine.

Smoking cigarettes and vaping are the most common ways to ingest nicotine, but someone can also misuse nicotine through transdermal patches, nicotine lozenges, and nicotine chewing gum.

How Does Nicotine Affect The Brain?

Seconds after ingesting nicotine, it enters the bloodstream and travels to the brain. Once in the brain, it triggers multiple neurotransmitters to produce feel-good sensations. The following are examples of the neurotransmitters that nicotine affects and their influence on the brain:

  • Dopamine makes someone feel pleasure and reward and reduces appetite.
  • Norepinephrine reduces appetite and produces arousal.
  • Acetylcholine increases cognitive functioning and arousal.
  • Glutamate enhances learning and memory.
  • Serotonin boosts mood and suppresses appetite.
  • Endorphins reduce anxiety, tension, and pain.
  • GABA reduces anxiety and stress.

Although nicotine is a stimulant, people associate it with feelings of calm, relaxation, less stress, and less anxiety because it produces euphoria and other rewarding sensations.

Nicotine leaves the body after several hours, depending on a person’s metabolism. As it leaves, the brain notices and wants to feel the effects of nicotine again. It then takes action, convincing you to continue smoking, chewing, or vaping.

Signs Of A Nicotine Addiction

Someone with a nicotine addiction continues to smoke, chew, or vape despite knowing the dangers and negative consequences they may face.

Every time nicotine enters the brain and produces rewarding sensations, it changes how the brain functions. Over time, the changes lead to addiction as the brain develops dependence and thinks it needs nicotine to survive.

The National Institute on Drug Abuse found approximately 23.6 million Americans have a nicotine use disorder.

The Diagnostic and Statistical Manual for Mental Disorders, Fifth Edition (DSM-5) lists specific criteria for diagnosing someone with a nicotine use disorder, including:

  • Using nicotine more than intended
  • Wanting to cut back or quit but being unable to
  • Spending a lot of time seeking or using nicotine
  • Failing to fulfill obligations due to nicotine use
  • Avoiding social activities to spend more time using nicotine
  • Continuing to use even though doing so worsens physical or psychological health
  • Continuing to use it even though it causes problems in relationships
  • Experiencing cravings and intense urges to use nicotine
  • Developing a tolerance to nicotine
  • Experiencing withdrawal symptoms when going without nicotine

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Symptoms Of Nicotine Withdrawal

One sign of nicotine addiction is withdrawal symptoms that appear when someone tries to quit using nicotine, which can be challenging and may interfere with daily functioning.

Withdrawal symptoms begin within a few hours after nicotine was last used and may include:

  • Irritability or agitation
  • Craving nicotine or having intense urges to use
  • Depression
  • Anxiety
  • Trouble thinking or concentrating
  • Memory problems
  • Sleep disturbances
  • Appetite changes

Some nicotine users may become addicted to the rituals associated with smoking, chewing, or vaping. For example, they smoke while driving, drinking their coffee, or after a meal. Many trigger cues exist for nicotine, making cravings intensify and relapse more likely.

Why Is Nicotine Dangerous?

Any use of nicotine can cause harmful effects on the body, including:

  • High blood pressure
  • Respiratory infections
  • Gastrointestinal problems
  • Lung injury
  • Exposure to metals and toxic solvents (through vaping)

Cigarette smoking is the leading cause of preventable disease, one that leads to disability and death. Currently, more than 16 million Americans are suffering from diseases they acquired related to using products containing nicotine, including:

  • Cancer
  • Heart disease
  • Stroke
  • Lung diseases
  • Diabetes
  • Chronic obstructive pulmonary disease (COPD)
  • Eye diseases
  • Tuberculosis
  • Gum disease
  • Sexual dysfunction
  • Weak immune system

Nicotine is dangerous when manufactured for cigarettes, e-cigarettes, chewing tobacco, and other products. The reason is that nicotine is combined with thousands of different chemicals for reasons like preservation, taste, and absorption. The added chemicals, when heated, transform into new chemicals that cause serious health risks.

One of the main chemicals present when smoking is carbon monoxide, which limits the oxygen that gets into your bloodstream and increases the amount of cholesterol that builds up in the arteries.

Second-hand smoke is another concern because it impacts the health of others. Research shows that second-hand smoke causes nearly 54,000 deaths annually. It can lead to asthma in young children living in homes where family members smoke and can increase the chances of lung disease in non-smokers by 20%.

Smoking During Adolescence

Adolescent nicotine use causes hormonal, neural, and psychosocial changes. It can lead to impulsivity and mood disorders. Early use of nicotine leads to teens misusing alcohol and drugs and developing a nicotine addiction that lasts into adulthood.

Smoking While Pregnant

Maternal nicotine use, pre- and post-natal, affects a baby’s birth weight, growth, and development. It also affects brain plasticity and may cause cleft palate, central auditory processing, and sudden infant death syndrome.

What Happens When You Quit Smoking?

As soon as someone quits smoking, the body begins to heal itself from the nicotine damage, and your taste, smell, lung function, and circulation improve.

Carbon monoxide levels return to normal as lungs begin to clean themselves of extra mucous from smoking. Breathing improves, and the longer someone goes without nicotine, the lower their risk of cancer, stroke, heart disease, or a cardiovascular event.

Get Help For Nicotine Addiction

If you are ready to conquer an addiction to nicotine, contact a treatment provider today. They can answer your questions and explore your treatment options to help get you on the path to a healthier, nicotine-free future.