Based on current data, the cost of a 7-day course of phenytoin (Dilantin) was $37.50 vs. $480 for a 7-day course of levetiracetam (Keppra).
The cost-utility analysis was conducted from the perspective of a university, level 1 urban trauma center, assuming that all patients with traumatic brain injury survived to receive 7 days of either agent to prevent posttraumatic seizures.
Base case assumptions were that all phenytoin patients would receive 1 g fosphenytoin (Cerebyx) intravenous load on day 0 plus 3 days of 100 mg phenytoin every 8 hours and that all levetiracetam patients would receive 500-mg load IV on day 0, followed by 7 days of 500 mg every 12 hours IV. Phenytoin patients would have a free phenytoin level drawn on day 3, with therapeutic patients receiving 100 mg phenytoin every 8 hours from post injury days 4 through 7 and subtherapeutic patients receiving an increased dose of phenytoin 200 mg every 8 hours from days 4 through 7.
The authors pointed out that they chose the smallest, least-expensive intravenous dosing for the levetiracetam arm and the most-expensive intravenous dosing for the phenytoin arm.
Quality-adjusted life years (QALY) were 23.6 for phenytoin and 23.2 for levetiracetam. As a result, the cost/effectiveness ratios were $1.58/QALY for phenytoin and $20.72/QALY for levetiracetam, according to Dr. Cotton, with the University of Texas at Houston, and his colleagues.
Dr. Terence O’Keeffe and his colleagues reported no conflicts of interest.
Dr. Cotton disclosed grant/research support from Haemonetics Corp. for a multicenter trial of rapid thrombelastography.