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Smoking and Other Tobacco Use


Judith J. Prochaska

, PhD, MPH, Stanford Prevention Research Center, Stanford University

Reviewed/Revised Nov 2023
Topic Resources

Tobacco use is a major individual and public health problem. Using tobacco is harmful to almost every organ in the body.

Tobacco is used because of the effects of nicotine. Nicotine is highly addictive when inhaled into the lungs. Cigarette smoking, which is the most harmful form of tobacco use, is the most common form used by adults. E-cigarettes Vaping Vaping refers to inhaling vapor (volatilized liquid) produced by battery-powered devices. The vapor can contain nicotine, tetrahydrocannabinol (THC) and cannabinoid (CBD) oils, and other substances... read more are the most common form of tobacco use among teens. A small percentage of people who smoke use cigars or pipes (including hookah). Some people use oral tobacco products such as chew and dip.

When smoking cigarettes, nicotine reaches the brain rapidly (within 10 seconds) and is highly addictive. In addition to nicotine, cigarettes contain tar and carbon monoxide, along with almost 4,000 other ingredients, many of which are toxic. These tobacco ingredients cause significant risk of disease and death.

Cigarette smoking remains the leading cause of preventable disease and death in the United States and globally. About 2 in 3 people who smoke long term will die prematurely of a disorder caused by smoking. Over half a million Americans die each year from a tobacco-related disease: that is, 1 in 5 deaths in the United States are related to smoking. Smoking is deadly because people who smoke inhale hundreds of substances, many of which can cause cancer Overview of Cancer , heart disease Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) Acute coronary syndromes result from a sudden blockage in a coronary artery. This blockage causes unstable angina or a heart attack (myocardial infarction), depending on the location and amount... read more Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) , and lung disease Chronic Obstructive Pulmonary Disease (COPD) . Smokeless tobacco products are not safe alternatives to smoking because they also contain toxins.

Although most nicotine exposure is from smoking tobacco, children may accidentally ingest nicotine (usually by eating cigarettes or butts left in ashtrays or sometimes nicotine gum, patches, or e-liquid).

Additionally, smoking is the most common cause of unintentional home fires in the United States. The Federal Emergency Management Agency (FEMA) estimates that about 7,800 smoking-related fires occur in residential buildings each year, causing about 275 deaths, 750 injuries, and $361 million in property loss. (See FEMA: Residential Building Smoking Fire Trends [2012-2021].)

Tobacco use in the United States has declined over the past 50 years. Yet, due to population growth, the absolute number of people who smoke in the United States has remained about the same at nearly 46 million adults. Cigarettes are marketed heavily, to adolescents as well as adults, primarily at the point of sale. Every day, about 1,600 youth under age 18 smoke their first cigarette, and nearly 200 youth start smoking daily.

Pregnant women and children

Smoking during pregnancy robs the developing fetus of oxygen and can cause low birth weight, preterm birth, and fetal death. Smoking during pregnancy also increases risk of sudden infant death syndrome (SIDS) Sudden Infant Death Syndrome (SIDS) Sudden infant death syndrome is the sudden, unexpected death, usually during sleep, of a seemingly healthy infant between 1 month and 1 year of age. The cause of sudden infant death syndrome... read more . Smoking is a pediatric disease: 9 in 10 adults who smoke started before the age of 18, which is prime time for brain development.

Symptoms of Tobacco Use

Smoking is harmful to almost every organ in the body.

Immediate effects

Nicotine is a stimulant that activates the pleasure center in the brain. When obtained through smoking, nicotine can increase energy and concentration and decrease appetite. Once a person is addicted, smoking will reduce symptoms of nicotine withdrawal and may feel relaxing. People not used to nicotine may have nausea, flushing, or both.

People who handle large amounts of tobacco leaves may absorb nicotine through their skin and develop nausea, vomiting, diarrhea, sweating, and weakness. This illness has been termed green tobacco sickness.

Children who eat tobacco products or nicotine gum or ingest e-liquid can develop nausea, vomiting, diarrhea, sweating, and weakness, along with agitation and confusion, sometimes from as little as one cigarette. However, serious or fatal toxicity in children is uncommon, in part because the vomiting empties the stomach. (See also American Association of Poison Control Centers: E-cigarettes and Nicotine.)

Long-term effects

The leading smoking-related health problems are the following:

Smoking also increases the risk of stroke Overview of Stroke A stroke occurs when an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue due to loss of its blood supply (cerebral infarction). Symptoms occur suddenly... read more , other cancers (such as bladder Bladder Cancer Most bladder cancers arise from the cells that form the innermost layer of the bladder. These cells, called transitional cells or urothelial cells, allow the bladder to stretch when it is full... read more , cervical Cervical Cancer Cervical cancer develops in the cervix (the lower part of the uterus). Most cervical cancers are caused by human papillomavirus (HPV) infection. Cervical cancer usually results from infection... read more Cervical Cancer , colorectal Colorectal Cancer Family history and some dietary factors (low fiber, high fat) increase a person’s risk of colorectal cancer. Typical symptoms include bleeding during a bowel movement, fatigue, and weakness... read more Colorectal Cancer , esophageal Esophageal Cancer Esophageal cancers develop in the cells that line the wall of the esophagus (the tube that connects the throat to the stomach). Tobacco and alcohol use, gastroesophageal reflux, and obesity... read more Esophageal Cancer , kidney Kidney Cancer Most solid kidney tumors are cancerous, but purely fluid-filled tumors (cysts) generally are not. Almost all kidney cancer is renal cell carcinoma. Another kind of kidney cancer, Wilms tumor... read more , liver Hepatocellular Carcinoma Hepatocellular carcinoma is a cancer that begins in the liver cells and is the most common of the primary liver cancers. Having hepatitis B or hepatitis C or fatty liver disease, or drinking... read more , pancreatic Pancreatic Cancer Smoking, chronic pancreatitis, obesity, and exposure to certain chemicals are risk factors for pancreatic cancer. Abdominal pain, weight loss, jaundice, and vomiting are some typical symptoms... read more , throat Mouth and Throat Cancer Mouth and throat cancers are cancers that originate on the lips, the roof, sides, or floor of the mouth, tongue, tonsils, or back of the throat. Mouth and throat cancers may look like open sores... read more Mouth and Throat Cancer , and stomach Stomach Cancer A Helicobacter pylori infection is a major risk factor for stomach cancer. Vague abdominal discomfort, weight loss, and weakness are some typical symptoms. Diagnosis includes endoscopy... read more Stomach Cancer ), pneumonia Overview of Pneumonia Pneumonia is an infection of the small air sacs of the lungs (alveoli) and the tissues around them. Pneumonia is one of the most common causes of death worldwide. The most common symptom of... read more Overview of Pneumonia and other respiratory infections, asthma Asthma Asthma is a condition in which the airways narrow—usually reversibly—in response to certain stimuli. Coughing, wheezing, and shortness of breath that occur in response to specific triggers are... read more Asthma , osteoporosis Osteoporosis Osteoporosis is a condition in which a decrease in the density of bones weakens the bones, making breaks (fractures) likely. Aging, estrogen deficiency, low vitamin D or calcium intake, and... read more Osteoporosis , periodontitis (gum disease) Periodontitis Periodontitis is a severe form of gingivitis, in which the inflammation of the gums extends to the supporting structures of the tooth. Plaque and tartar build up between the teeth and gums and... read more Periodontitis , peptic ulcer disease Peptic Ulcer Disease A peptic ulcer is a round or oval sore where the lining of the stomach or duodenum has been eaten away by stomach acid and digestive juices. Peptic ulcers can result from infection with Helicobacter... read more Peptic Ulcer Disease , cataracts Cataract A cataract is a clouding (opacity) of the lens of the eye that causes a progressive, painless loss of vision. Vision may be blurred, contrast may be lost, and halos may be visible around lights... read more Cataract , erectile dysfunction Erectile Dysfunction (ED) Erectile dysfunction (ED) is the inability to attain or sustain an erection satisfactory for sexual intercourse. (See also Overview of Sexual Dysfunction in Men.) Every man occasionally has... read more , and fertility problems Overview of Infertility Infertility is a disease defined by the inability to achieve a pregnancy and/or the need for medical intervention to achieve a successful pregnancy. Infertility is defined as disease by the... read more Overview of Infertility .

Secondhand smoke

People who do not smoke but who are exposed to smoke from a burning cigarette or the smoke exhaled by a nearby person (passive, or secondhand smoking) can develop many of the same disorders as people who smoke, particularly with repeated and sustained exposure. The U.S. Surgeon General concluded there is no safe level of secondhand smoke exposure.

Children exposed to cigarette smoke lose more school days because of illness than nonexposed children.

Smokeless tobacco


Other effects

Smoking can interact with medications. The effects are largely due to tars (a by-product of smoking) affecting the liver, and not due to the nicotine; hence, most effects are not seen with nicotine replacement therapy (NRT). Smoking dries and wrinkles a person's skin, thins the hair, and turns the teeth and fingers yellow. People who smoke tend to weigh about 10 pounds less than they would if they did not smoke, but not everyone gains weight when they quit smoking. Also, the harmful effects of smoking far outweigh the risks of weight gain. Employees who smoke cost employers on average over $5,000 more per year than nonsmoking employees due to greater health care costs and more missed days of work. Smoking increases the risk of unemployment and makes it harder to find re-employment.

Withdrawal symptoms

Nicotine withdrawal Nicotine Withdrawal Most people who smoke want to quit and have tried doing so with limited success. Effective tools to help quit smoking include counseling, nicotine replacement products, and medications. While... read more may result in many unpleasant symptoms, including a craving for nicotine, irritability, anxiety, poor concentration, restlessness, trembling (tremor), depressed mood, weight gain, headaches, drowsiness, and stomach upset. Withdrawal is most troublesome in people who are severely dependent. The symptoms of nicotine withdrawal peak in the first 3 days and subside over 2 to 4 weeks, but some symptoms, such as craving, may continue longer.

Diagnosis of Tobacco Use

  • Questions from health care professionals

It is recommended that health care professionals ask everyone about tobacco use. For many people, smoking is an addiction needing medical treatment. Assessing a person's quantity of use (the number of cigarettes smoked per day [presently and in the past]) and how soon they smoke upon waking up (within 30 minutes is a useful measure) can provide an indication of the severity of tobacco dependence and nicotine addiction. Responses also can help guide the choice of cessation medication and its dosing.

Nicotine poisoning can be overlooked. For example, children may swallow cigarettes or nicotine gum without being seen. Even when children are observed with tobacco in their mouth, it can be difficult to tell how much they have actually swallowed. People with green tobacco sickness may not connect their symptoms with handling tobacco.

Treatment of Tobacco Use

  • Treatment of symptoms

  • Quitting smoking

Emergency treatment is rarely required except for children who have eaten products that contain nicotine. Doctors sometimes give activated charcoal by mouth to absorb any nicotine remaining in the gastrointestinal tract. Children who are very agitated may be given a sedative such as lorazepam.

Stopping smoking Smoking Cessation Most people who smoke want to quit and have tried doing so with limited success. Effective tools to help quit smoking include counseling, nicotine replacement products, and medications. While... read more can be very difficult and relapse is common. Quitting successfully usually requires many attempts. Evidence-based treatments more than double the chances of long-term success.

More Information

The following English-language resources may be useful. Please note that The Manual is not responsible for the content of these resources.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Commit, Habitrol, Nicoderm CQ, NICOrelief , Nicorette, Nicotrol, Nicotrol NS
Ativan, Loreev XR
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