As is common with respiratory disease, smoking is believed to adversely affect asthmatics in several ways, including an increased severity of symptoms, a more rapid decline of lung function, and decreased response to preventive medications.

Automobile emissions are considered an even more significant cause and aggravating factor. asthma who smoke or who live near trade typically require additional medications to help control their disease.

Furthermore, exposure of the two non-smokers and smokers to wood smoke, gas stove fumes and second-hand smoke is detrimental, resulting in more severe asthma, in addition emergency chamber visits, and more asthma-related hospital admissions.

Smoking cessation and avoidance of second-hand smoke is strongly encouraged in asthmatics.