Discontinuing the practice of inhaling a tobacco smoking. You can quit smoking without assistance from health care professionals or the use of medications. Methods that have been found to be effective include interventions aimed at health care providers and health care systems; medications including nicotine replacement therapy (NRT) and varenicline; individual and group counseling; and Web-based and computer programs. Although stopping smoking can cause side effects such as weight gain, smoking cessation programs are cost-effective because of the positive health benefits.

Cigarettes contain tobacco which contains the chemical nicotine. Smoking cigarettes can lead to nicotine addiction. The addiction begins when nicotine acts on nicotinic acetylcholine receptors to release neurotransmitters such as dopamine, glutamate, and gamma-aminobutyric acid. Cessation of smoking leads to symptoms of nicotine withdrawal such as anxiety and irritability. Methods of smoking cessation must address nicotine addiction and nicotine withdrawal symptoms.

• Within 20 minutes after quitting, blood pressure and heart rate decrease
• Within 12 hours, carbon monoxide levels in the blood decrease to normal
• Within 3 months, circulation and lung function improve
• Within 9 months, there are decreases in cough and shortness of breath
• Within 1 year, the risk of coronary heart disease is cut in half
• Within 5 years, the risk of stroke falls to the same as a non-smoker, and the risks of many cancers (mouth, throat, esophagus, bladder, cervix) decrease significantly
• Within 10 years, the risk of dying from lung cancer is cut in half,[123] and the risks of larynx and pancreas cancers decrease
• Within 15 years, the risk of coronary heart disease drops to the level of a non-smoker