Premenstrual asthma (PMA) is a clinical picture with worsening of asthmatic symptoms and pulmonary functions in the late luteal phase of the menstrual cycle. The aim of this study was to evaluate the inflammatory changes in asthmatic women who complain of PMA. Forty asthmatic women attending our outpatient clinic were questioned about worsening of their asthma before menstruation. Eleven women (aged 17-40) who complained of PMA participated in the study. Subjects were asked to record peak expiratory flow rates, symptom scores, and beta-agonist use daily. After the first menses on the seventh day of their cycle, and before the onset of the next menstruation, on the 26+/-3rd day of the cycle, patients were evaluated with pulmonary function tests, methacholine challenge test, and fractionated exhaled nitric oxide (FE(NO)) levels. Eosinophils in peripheral blood and induced sputum were also evaluated. When comparing the two groups of results, the significant changes were in FENO levels, day-time symptom scores, and eosinophils in induced sputum (29.25 ppb/9.16 ppb p < 0.05, 1/0.45 p = 0.05, %6.63/%4.09 p < 0.01, respectively, before and after menstruation). These results show that PMA is not only a clinical picture with a decrease in airway calibre that can be related to the regulation of 2 receptors, but also a complex state with worsening of airway inflammation.