The effect of careful follow-up and treatment modification for 45 patients with an admission for NFA has been studied. In 24 of 45, inciting events were recognized. BDP was used by 14 patients pre-NFA. In the mean follow-up of 863 days, there have been no deaths and seven patients have been readmitted with asthma. Six of the 45 patients have attained normal FEV1 and PC20H. Blunted perception of breathlessness, change in VAS ratio/change in FEV1, was found when first measured, but normalized to be no different than that of other asthmatic subjects as airway responsiveness became milder. The CO2 ventilatory responses did not differentiate individual NFA patients from non-NFA asthmatic or normal subjects. Comparison of the NFA cohort with the 1985 asthma admission cohort showed that an asthma admission within the last five years was a risk factor for a NFA episode.