OBJECTIVES: To assess the economic burden and health care utilizations of asthma patients in the U.S. Medicare population.  METHODS: A retrospective analysis was conducted using national Medicare data (01JAN2008-31DEC2010). All Medicare beneficiaries diagnosed with asthma were identified using International Classification of Disease, 9^th Revision, Clinical Modification (ICD-9-CM) code 493.xx. The first asthma diagnosis date was designated as the index date. Patients were required to have 12 months continuous enrollment pre- and post-index date. Comorbid conditions were examined for the baseline period. Study outcomes including treatment patterns within 60 days after the index date, health care utilization and costs in the Medicare research identifiable file during the follow-up period were measured.  RESULTS: A total of 63,012 patients were identified for study, of which the majority was White (84.7%), male (68.2%) and resided in the Southern U.S. region (38.3%). The mean age of patients was 76 years. The Charlson Comorbidity Index score was 2.39, and common comorbidities included chronic obstructive pulmonary disease (42.9%), diabetes (33.2%) and tumor (30.2%). Patients were more often prescribed albuterol sulfate (19.1%), hydrocodone bitartrate/acetaminophen (14.4%) and furosemide (13.1%). Health care utilizations included Medicare carrier use (99.0%), Durable Medical Equipment (DME, 51.7%), Home Health Agency (HHA, 22.3%), outpatient visits (81.6%) and inpatient (40.8%), Skilled Nursing Facility (SNF, 12.6%) and hospice admissions (5.0%) and prescription drug (part D event) claims (57.3%). Patient expenditures were calculated at $5,431 for Carrier, $726 for DME, $1,401 for HHA, $15,211 for outpatient, $9,162 for inpatient, $2,354 for SNF, $464 for hospice, $2,192 for pharmacy and $36,941 for total costs.  CONCLUSIONS: U.S. Medicare patients diagnosed with asthma were more often prescribed albuterol sulfate, experienced a high percentage of Medicare carrier service use and outpatient visits, as well as frequent comorbidities, which translated into high total health care expenses as evidenced by this study.