I read with great interest the article by Sarasin et al1 in the October 9, 2000, issue of the ARCHIVES. The authors have performed a thorough analysis of the cost-effectiveness of emerging antiplatelet therapies. A review of their data, however, reveals a point that will be particularly important for North American physicians. The authors cite "current market prices" (which I assume represent prices in Switzerland and Germany) as their source for the daily costs of aspirin with or without dipyridamole, resulting in a daily cost of the aspirin/dipyridamole combination of $0.60. The average US wholesale price for this medication, however, is $1.47 for the 25 mg/200 mg formulation, or roughly $2.95 for the dosage analyzed in the study.2 This is far outside the values used in their sensitivity analysis. The authors note that at a daily cost of $1.20 this regimen goes from a cost savings to a cost-effectiveness ratio of $3630 per quality-adjusted life-year. I calculate that this $0.60 increase from the base case cost adds an additional $4060 to the total cost of the aspirin/dipyridamole arm of their analysis. If one assumes a daily cost of $2.40, this would raise the total cost for this strategy by a total of $12 180, to $53 605. Thus, at a price approaching the average US wholesale price for aspirin/dipyridamole, its cost-effectiveness ratio is $30 697. This points out the importance of adjusting data used in cost-effectiveness analyses to reflect local prices because a therapy that is cost savings using what I presume to be Swiss prices has a significant cost increase when using the average US wholesale price.