Parkinson's disease (PD), a neurological syndrome characterized by resting tremors, muscle rigidity, postural instability and bradykinesia, affects nearly 1 million people in the United States. Few studies have investigated the costs for health care services related to this disease. OBJECTIVE: To report the utilization and costs for medical services and prescription medications for PD in a state Medicaid population. METHODS: Medicaid administrative claims dated from January 1, 2002 through December 31, 2002 for medical services (hospitalizations, emergency department visits, outpatient visits, and nursing home admissions) with a primary or secondary ICD-9 diagnosis code for PD were extracted. Unique and anonymous recipient codes from these claims were used to extract prescription claims for drugs used for palliative treatment of PD. Costs reported were from the perspective of Medicaid. RESULTS: There were 11,919 recipients identified with PD. Of these, a total of 11,785 (99%) recipients had claims for nursing home care. The average length of stay in the nursing home was 222 days with an average cost of $27,950 per stay. Only 618 recipients (5%) had claims for an outpatient visit related to PD, and there were very few ED and hospital visits for PD. Outpatient prescription costs for drugs related to PD totaled $501,941, with an average cost of $63 per prescription. Carbidopa/levodopa (62.5%), pramipexole (8%), and ropinirole (4%) accounted for the majority of prescriptions dispensed. The costs for these drugs were $269,020 for carbidopa/levodopa, $91,359 for pramipexole, and $33,920 for ropinirole. CONCLUSION: Among recipients covered by Medicaid, a majority of health care services utilized for the treatment of PD were for nursing home care followed by prescription medications. The results indicated that long-term care and palliative drug treatment were the major contributors of total dollars spent by Medicaid for care of its recipients with PD.