Question: how nicotine effects the brain

Reference:
 Nicotine dependence Overview Nicotine dependence -- also called tobacco dependence -- is an addiction to tobacco products caused by the drug nicotine. Nicotine dependence means you can't stop using the substance, even though it's causing you harm. Nicotine produces physical and mood-altering effects in your brain that are temporarily pleasing. These effects make you want to use tobacco and lead to dependence. At the same time, stopping tobacco use causes withdrawal symptoms, including irritability and anxiety. While it's the nicotine in tobacco that causes nicotine dependence, the toxic effects of tobacco result from other substances in tobacco. Smokers have much higher rates of heart disease, stroke and cancer than nonsmokers do. Regardless of how long you've smoked, stopping smoking can improve your health. Many effective treatments for nicotine dependence are available to help you manage withdrawal and stop smoking for good. Ask your doctor for help. Symptoms For some people, using any amount of tobacco can quickly lead to nicotine dependence. Signs that you may be addicted include: - You can't stop smoking. You've made one or more serious, but unsuccessful, attempts to stop. - You experience withdrawal symptoms when you try to stop. Your attempts at stopping have caused physical and mood-related symptoms, such as strong cravings, anxiety, irritability, restlessness, difficulty concentrating, depressed mood, frustration, anger, increased hunger, insomnia, constipation or diarrhea. - You keep smoking despite health problems. Even though you've developed health problems with your lungs or your heart, you haven't been able to stop. - You give up social or recreational activities in order to smoke. You may stop going to smoke-free restaurants or stop socializing with certain family members or friends because you can't smoke in these locations or situations. You're not alone if you've tried to stop smoking but haven't been able to stop for good. Most smokers make many attempts to stop smoking before they achieve stable, long-term abstinence from smoking. You're more likely to stop for good if you follow a treatment plan that addresses both the physical and the behavioral aspects of nicotine dependence. Using medications and working with a counselor specially trained to help people stop smoking (a tobacco treatment specialist) will significantly boost your chances of success. Ask your doctor, counselor or therapist to help you develop a treatment plan that works for you or to advise you on where to get help to stop smoking. Causes Nicotine is the chemical in tobacco that keeps you smoking. Nicotine is very addictive when delivered by inhaling tobacco smoke into the lungs, which quickly releases nicotine into the blood allowing it to get into the brain within seconds of taking a puff. In the brain nicotine increases the release of brain chemicals called neurotransmitters, which help regulate mood and behavior. Dopamine, one of these neurotransmitters, is released in the "reward center" of the brain and causes improved mood and feelings of pleasure. Experiencing these effects from nicotine is what makes tobacco so addictive. Nicotine dependence involves behavioral (routines, habits, feelings) as well as physical factors. These behavioral associations with smoking may act as triggers - situations or feelings that activate a craving for tobacco, even if you have not smoked for some time. Behaviors and cues that you may associate with smoking include: - Certain times of the day, such as first thing in the morning, with morning coffee or during breaks at work - After a meal - Drinking alcohol - Certain places or friends - Talking on the phone - Stressful situations or when you're feeling down - Sight or smell of a burning cigarette - Driving your car To overcome your dependence on tobacco, you need to become aware of your triggers and develop a plan to deal with the behaviors and routines that you associate with smoking. Risk factors Anyone who smokes or uses other forms of tobacco is at risk of becoming dependent. Factors that influence who will use tobacco include: - Genetics. The likelihood that you will start smoking and keep smoking may be partly inherited - genetic factors may influence how receptors on the surface of your brain's nerve cells respond to high doses of nicotine delivered by cigarettes. - Home and peer influence. Children who grow up with parents who smoke are more likely to become smokers. Children with friends who smoke also are more likely to try cigarettes. Evidence suggests that smoking shown in movies and on the Internet can encourage young people to smoke. - Age. Most people begin smoking during childhood or the teen years. The younger you are when you begin smoking, the greater the chance that you'll become a heavy smoker as an adult. - Depression or other mental illness. Many studies show an association between depression and smoking. People who have depression, schizophrenia, post-traumatic stress disorder (PTSD) or other forms of mental illness are more likely to be smokers. - Substance use. People who abuse alcohol and illegal drugs are more likely to be smokers. Complications Tobacco smoke contains more than 60 known cancer-causing chemicals and thousands of other harmful substances. Even "all natural" or herbal cigarettes have chemicals that are harmful to your health. Smoking harms almost every organ of your body and impairs your body's immune system. About half of all regular smokers will die of a disease caused by tobacco. Women smokers are now at equal risk to men smokers of dying from lung cancer, COPD and cardiovascular disease caused by using tobacco. The negative health effects include: - Lung cancer and other lung diseases. Smoking causes nearly 9 out of 10 lung cancer cases. In addition, smoking causes other lung diseases, such as emphysema and chronic bronchitis. Smoking also makes asthma worse. - Other cancers. Smoking is a major cause of cancers of the esophagus, larynx, throat (pharynx) and mouth and is related to cancers of the bladder, pancreas, kidney and cervix, and some leukemias. Overall, smoking causes 30 percent of all cancer deaths. - Heart and circulatory system problems. Smoking increases your risk of dying of heart and blood vessel (cardiovascular) disease, including heart attack and stroke. Even smoking just one to four cigarettes daily increases your risk of heart disease. If you have heart or blood vessel disease, such as heart failure, smoking worsens your condition. However, stopping smoking reduces your risk of having a heart attack by 50 percent in the first year. - Diabetes. Smoking increases insulin resistance, which can set the stage for the development of type 2 diabetes. If you have diabetes, smoking can speed the progress of complications, such as kidney disease and eye problems. - Eye problems. Smoking can increase your risk of serious eye problems such as cataracts and loss of eyesight from macular degeneration. - Infertility and impotence. Smoking increases the risk of reduced fertility in women and the risk of impotence in men. - Pregnancy and newborn complications. Mothers who smoke while pregnant face a higher risk of miscarriage, preterm delivery, lower birth weight and sudden infant death syndrome (SIDS) in their newborns. - Cold, flu and other illnesses. Smokers are more prone to respiratory infections, such as colds, flu and bronchitis. - Weakened senses. Smoking deadens your senses of taste and smell, so food isn't as appetizing. - Teeth and gum disease. Smoking is associated with an increased risk of developing inflammation of the gum (gingivitis) and a serious gum infection that can destroy the support system for teeth (periodontitis). - Physical appearance. The chemicals in tobacco smoke can change the structure of your skin, causing premature aging and wrinkles. Smoking also yellows your teeth, fingers and fingernails. - Risks to your family. Nonsmoking spouses and partners of smokers have a higher risk of lung cancer and heart disease compared with people who don't live with a smoker. If you smoke, your children will be more prone to SIDS, worsening asthma, ear infections and colds. Diagnosis Your doctor may ask you questions or have you complete a questionnaire to get a sense of how dependent you are on nicotine. The more cigarettes you smoke each day and the sooner you smoke after awakening, the more dependent you are. Knowing your degree of dependence will help your doctor determine the best treatment plan for you. Treatment Like most smokers, you've probably made at least one serious attempt to stop. But it's rare to stop smoking on your first attempt - especially if you try to do it without help. You're much more likely to stop if you use medications and counseling, which have both been proved effective, especially in combination. Medications Many treatments, including nicotine replacement therapy and non-nicotine medications, have been approved as safe and effective in treating nicotine dependence. Using more than one medication may help you get better results. For example, combining a longer acting medication with a short-acting nicotine replacement product may be beneficial. Talk to your health care provider about the right treatment for you. If you're pregnant or breast-feeding, you smoke fewer than 10 cigarettes a day, or you're under age 18, talk to your doctor before taking any over-the-counter nicotine replacement products. Nicotine replacement therapy Nicotine replacement therapy gives you nicotine without tobacco and the harmful chemicals in tobacco smoke. Nicotine replacement products help relieve withdrawal symptoms and cravings. The best time to start using nicotine replacement medication is on the date you've set to stop smoking. Some smokers start earlier in order to reduce smoking on their way to stopping altogether. The following nicotine replacement products are available over-the-counter: - Nicotine patch (NicoDerm CQ, Habitrol, others). The patch delivers nicotine through your skin and into your bloodstream. You wear a new patch each day. You typically use the patch for eight weeks or longer. If you haven't been able to stop smoking completely after two weeks of wearing the patch, ask your doctor about adjusting the dose or adding another nicotine replacement product. Common side effects include skin irritation, insomnia and vivid dreams. - Nicotine gum (Nicorette, others). This gum delivers nicotine to your blood through the lining of your mouth. Nicotine gum is often recommended to curb cravings. Chew the gum for a few times until you feel a mild tingling or peppery taste, then park the gum between your cheek and gumline for several minutes. This chewing and parking allows nicotine to be gradually absorbed in your bloodstream. Mouth irritation is a common side effect. Other side effects are often a result of overly vigorous chewing that releases nicotine too quickly. These include heartburn, nausea and hiccups. - Nicotine lozenge (Commit, Nicorette mini lozenge, others). This lozenge dissolves in your mouth and, like nicotine gum, delivers nicotine through the lining of your mouth. Place the lozenge in your mouth between your gumline and cheek or under your tongue and allow it to dissolve. You'll start with one lozenge every one to two hours and gradually increase the time between lozenges. Avoid drinking anything right before, while using or right after the lozenge. Side effects include mouth irritation as well as nicotine-related effects such as heartburn, nausea and hiccups. These nicotine replacement products are available by prescription: - Nicotine nasal spray (Nicotrol NS). The nicotine in this product, sprayed directly into each nostril, is absorbed through your nasal membranes into your blood vessels. The nasal spray delivers nicotine a bit quicker than gum, lozenges or the patch, but not as rapidly as smoking a cigarette. It's usually prescribed for three-month periods for up to six months. Nasal and throat irritation, runny nose, sneezing and coughing are common side effects. - Nicotine inhaler (Nicotrol). This device is shaped something like a cigarette holder. You puff on it, and it delivers nicotine vapor into your mouth. You absorb the nicotine through the lining in your mouth, where it then enters your bloodstream. Common side effects are mouth and throat irritation and occasional coughing. Non-nicotine medications Medications that don't contain nicotine and are available by prescription include: - Bupropion (Zyban). The antidepressant drug bupropion increases levels of dopamine and norepinephrine, brain chemicals that are also boosted by nicotine. Typically your doctor will advise you to start bupropion one week before you stop smoking. Bupropion has the advantage of helping to minimize weight gain after you quit smoking. Common side effects include insomnia, agitation, headache and dry mouth. If you have a history of seizures or serious head trauma, such as a skull fracture, you shouldn't take this drug. - Varenicline (Chantix). This medication acts on the brain's nicotine receptors, decreasing withdrawal symptoms and reducing the feelings of pleasure you get from smoking. Typically your doctor will advise you to start varenicline one week before you stop smoking. Common side effects include nausea, headache, insomnia and vivid dreams. Rarely, varenicline has been associated with serious psychiatric symptoms, such as depressed mood and suicidal thoughts. - Nortriptyline (Pamelor). This medication may be prescribed if other medications haven't helped. This tricyclic antidepressant acts by increasing the levels of the brain neurotransmitter norepinephrine. Common side effects may include dry mouth, drowsiness, dizziness and constipation. Counseling, support groups and other programs Combining medications with behavioral counseling provides the best chance for establishing long-term smoking abstinence. Medications help you cope by reducing withdrawal symptoms including tobacco craving, while behavioral treatments help you develop the skills you need to avoid tobacco over the long run. The more time you spend with a counselor, the better your treatment results will be. Several types of counseling and support can help with stopping smoking: - Telephone counseling. No matter where you live, you can take advantage of phone counseling to help you give up tobacco. Every state in the U.S. has a telephone quit line, and some have more than one. To find the options in your state, call 800-QUIT-NOW (800-784-8669). - Individual or group counseling program. Your doctor may recommend local support groups or a treatment program where counseling is provided by a tobacco treatment specialist. Counseling helps you learn techniques for preparing to stop smoking and provides support for you during the process. Many hospitals, health care plans, health care providers and employers offer treatment programs or have tobacco treatment specialists who are certified to provide treatment for nicotine dependence. Nicotine Anonymous groups are available in many locations to provide support for smokers trying to quit. Some medical centers provide residential treatment programs - the most intensive treatment available. - Internet-based programs. Several websites offer support and strategies for people who want to stop smoking. BecomeAnEX is free and provides information and techniques as well as blogs, community forums, ask the expert and many other features. Text messaging services, including personalized reminders about a quit-smoking plan, also may prove helpful. Methods to avoid It's not a good idea to substitute another type of tobacco use for cigarette smoking. Tobacco in any form is not safe. Even products that deliver nicotine without tobacco are risky. Stick with proven stop-smoking aids and steer clear of the following products: - Dissolvable tobacco products. Tobacco pouches, lozenges, strips or other products contain small amounts of tobacco and nicotine you hold or dissolve in your mouth. There is no evidence they will help you stop smoking and little is known about their health effects. - E-cigarettes. Electronic cigarettes, or e-cigarettes, are battery-powered devices that heat liquid containing nicotine into a vapor to be inhaled. Because these products are new, there isn't much data about possible safety risks. Studies of e-cigarettes for smoking cessation have shown mixed results. For these reasons, e-cigarettes aren't recommended for people trying to quit smoking. - Flavored cigarettes. Clove cigarettes (kreteks) and flavored cigarettes (bidis) carry the same health risks as smoking regular cigarettes and can cause additional health problems. Although they're banned in the United States, flavored cigarettes are available in other countries. - Hookahs (narghiles). These are water pipes that burn tobacco, and the smoke is inhaled through a hose. They are not safer than cigarettes. The water does not filter out toxins in the smoke, and the water and pipe have a risk of transmitting infections. - Nicotine lollipops and balms. Products containing nicotine salicylate are not approved by the Food and Drug Administration, and they pose a risk for accidental use by children. - Pipes and cigars. These products have similar, though less frequent, health risks as cigarettes, and they are not a safe alternative. - Smokeless tobacco and snuff (snus). These products contain nicotine in amounts similar to cigarettes and increase your risk of mouth and throat cancer, tooth and gum diseases, and other health problems. Lifestyle and home remedies It's important to have a plan for managing nicotine withdrawal symptoms. Withdrawal symptoms are usually the most intense during the first week after you stop smoking. They may continue for several weeks, with declining intensity. Although most nicotine withdrawal symptoms pass within a month, you may occasionally experience a strong urge or craving to smoke months after stopping. Triggers or cues that were associated with your smoking can provoke these urges or cravings. Here's what you can do to help manage nicotine withdrawal symptoms: - Exercise regularly. Regular physical activity has been found to reduce withdrawal symptoms and help people stop smoking. Exercise also helps avoid potential weight gain often associated with stopping. - Wait out cravings. Cravings or urges usually last less than five minutes. Wash the dishes, go for a walk or have a healthy snack, such as carrots, an apple or sunflower seeds, which will keep your mouth busy. Do something that keeps your hands busy, and before you know it, the urge will have passed. This is why you want to get rid of tobacco supplies when you decide to quit. You don't want to have any on hand when a craving hits. - Identify rationalizations. If you find yourself thinking, "I'll just smoke one to get through this tough time" or "Just one won't hurt," recognize it as a message that can derail your plan. Review your reasons for quitting, and replace that thought with something positive to support your stopping. - Talk to a support person. If you're feeling anxious or depressed or need encouragement, a support person can help you get through a difficult craving. - Avoid high-risk situations. Know your triggers, and stay away from people, places and situations that tempt you to smoke. - Eat regular, healthy meals. Include plenty of fruits and vegetables, and drink more water. Alternative medicine Many products claim to be smoking-cessation aids. Many also claim to be "natural." Just remember that "natural" doesn't necessarily mean "safe." Talk with your doctor before trying any alternative medicine treatments. - Acupuncture. Acupuncture involves stimulating points on the body, typically with thin, solid, metallic needles. Several studies have been conducted on the effects of acupuncture or acupressure for smoking cessation, but there's no definitive evidence that it works. - Herbs and supplements. A few studies have been conducted on the dietary supplements SAMe, silver acetate and St. John's wort for the treatment of tobacco dependence, but there is no current evidence that any natural product improves smoking cessation rates. - Hypnosis. Although no evidence supports the use of hypnosis - also called hypnotherapy - in smoking cessation, some people find it helpful. If you choose to pursue hypnosis, talk to your doctor about finding a reputable therapist. - Meditation. Although no evidence supports the effectiveness of meditation in smoking cessation, some people find it helpful to reduce symptoms of anxiety. 

Answer: Nicotine produces physical and mood-altering effects in your brain that are temporarily pleasing. These effects make you want to use tobacco and lead to dependence. Nicotine is very addictive when inhaled into the lungs via tobacco smoke. This allows nicotine to get into the brain within seconds of taking a puff. Once in the brain, nicotine increases the release of chemicals which help to regulate mood and behavior. This include dopamine, which is released in the reward center of the brain, causing improvements in mood and behavior. Experiencing these effects is what makes nicotine so addictive.