OBJECTIVES:  Medications are critical for preventing and controlling migraine headaches. The objectives of this project are to describe anti-migraine drug (AMD) utilization, price and reimbursement trends, and to compare market share competitions between Ergots and serotonin 5-HT1 receptor agonists (triptans). METHODS:  Study drugs included ergot derivatives and triptans. A retrospective, descriptive time-series analysis was conducted for this study. The data source is the national Medicaid pharmacy claim database from CMS. The quarterly prescription numbers and reimbursement amounts were calculated from 1st quarter 1991 to 4th quarter 2008. The quarterly per-prescription reimbursements were defined as total reimbursement amounts divided by total prescriptions. The market shares were calculated based on the proportion of total prescription numbers. RESULTS:  The total reimbursement for AMDs increased from $1.6 million in 1991 to $156 million in 2004, and dropped to $115 million in 2008. Prescriptions for AMDs increased from 56,410 in 1991 to 948,597 in 2004, and then dropped to 542,093 in 2008. The ergot prescriptions increased from 25,540 in 1991 to 47,543 in 1995, then gradually decreased to 6,367 in 2008. A similar utilization trend was found for ergot combination products. Meanwhile, triptan prescriptions increased from 23,523 in 1995 to 912,978 in 2004, and dropped to 524,922 in 2008. The market share for triptans increased dramatically from 0% in 1994 to 97% in 2008, while the market share for ergot derivatives and ergot combination products decreased from 45% and 55% in 1991 to 1% and 2% in 2008, respectively. The per-prescription cost of branded triptans has steadily increased since 1994, regardless of newer brand entries. CONCLUSIONS:  Triptan use has increased dramatically and dominated the AMD market. However, triptan utilization dropped 34.91% in 2006. This may be due to the implementation of Medicare Part D.