There will be a period of withdrawal symptoms after quitting smoking after 40 years of smoking, but the withdrawal symptoms will basically disappear completely after about 3 months. Withdrawal symptoms usually refer to the various symptoms that drug addicts experience for a period of time after decreasing or stopping the dosage of a drug, including insomnia, euphoria, tearfulness, sweating, tremors, diarrhea, vomiting, and other symptoms. For 40 years of smoking age after quitting smoking people will also appear certain withdrawal symptoms, but generally only in a week more obvious, usually in about 3 months basically disappear, there are some people will be longer, but adhere to the smoking cessation is beneficial to health. Therefore, for people who have smoked for a long time, it is recommended to actively adhere to the smoking cessation, ensure a certain amount of exercise and maintain a good diet and routine, which is beneficial to the health of the body.