Nonspecific nasal reactivity and smoking.

Twenty-three smoking and twenty-four nonsmoking patients both with and without symptomatic rhinitis and/or atopy were challenged intranasally with histamine. Histamine sensitivity was measured by changes in flow rates assessed by anterior rhinomanometry. The median threshold for both smokers and nonsmokers was 0.4 mg histamine. Small numbers limited the analyses of the subgroups. The data did not suggest that cigarette smoke increases nonspecific nasal reactivity as measured by histamine challenge.