Dizziness after smoking may be caused by nicotine and nicotine. Infrequent smokers or first-time smokers may experience a toxic reaction due to poor tolerance to nicotine, which can lead to dizziness, nausea, vomiting, and sphincter relaxation due to the excessive amount of nicotine dissolved into the bloodstream. In the room where second-hand smoke accumulates, due to the lack of air circulation, harmful substances such as nicotine and carbon monoxide enter the human body and lead to the emergence of a toxic reaction, which can lead to dizziness, headache, and even coma and other symptoms. In addition, smoking too much at one time, the production of nicotine, nicotine and other stimulation of the nerves, can also appear dizziness symptoms. Nicotine poisoning cerebral vasodilatation, head capillary permeability increases, this time there will be dizziness symptoms, there may also be nausea and vomiting feeling, usually lasts for ten minutes, or even longer, serious cases will be life-threatening. It is recommended that patients actively seek medical attention so as not to delay their condition.