OBJECTIVES: The purpose of this abstract is to examine the use of long-term asthma controller medications (LTACM) before and after asthma-related inpatient stays and emergency department events (EDE). METHODS: Data wAS drawn from the 1997 Medstat-Marketscan claims database. Asthma-related events were defined as EDE or inpatient hospital stay with a primary or secondary diagnosis of asthma (ICD-9 code 493). LTACM included corticosteroids, xanthines, leukotriene modifiers and combination medications. RESULTS: The sample included 464 individuals with an asthma-related EDE and 747 with an inpatient hospital stay. Of the EDE sample, 60% filled a prescription for LTACM during the calendar year. A total of 32% had filled a prescription prior to the EDE with an average of 85 days between the prescription being filled and the EDE. Twenty percent filled a prescription during the month subsequent to the EDE and 35% during the subsequent calendar year. Of those with a hospital stay, 60% filled a prescription for LTACM during the calendar year. Of those that filled a prescription prior to the hospitalization, there was an average of 70.4 days between the filling of the prescription and the event. Forty four percent of the hospital sample filled a prescription afterward, with 65% doing so within 30 days. CONCLUSIONS: We find that many of those receiving care in inpatient ad emergency departments are not using long-term controller medications. It is likely that virtually all of these individuals have been prescribed medications, but have not complied with the drug regimen. Even after an adverse event, a slight majority continues to not fill prescriptions. One approach for improving the health of those with asthma and reducing asthma expenditures