Objective. To investigate the role of initial nonsteroidal antiinflammatory drug (NSAID) choice in the prevention of NSAID gastropathy, based on relative clinical and economic effects. Methods. To mimic clinical practice, a symptom-driven decision analytic model was constructed to compare 2 treatment strategies for long-term users of NSAIDs over a 1-year period: Strategy 1-generic NSAID used initially, and safer, more expensive NSAID reserved for treatment failures due to symptomatic gastropathy; and Strategy 2-safer, more expensive NSAID used in all instances. The only distinction between the strategies was the choice of initial NSAID. NSAIDs differed in gastrointestinal safety profiles and acquisition costs. The use and impact of antisecretory medications were included in the model. Because published data on patients' ulcer risk and relative NSAID safety show considerable variability, sensitivity analyses were used to evaluate the key clinical outcomes and costs. Result. For patients without risk factors for NSAID ulcers (average risk), the model estimated that the strategy restricting use of the safer NSAID resulted in more symptomatic ulcers (Strategy 1, 2.58; Strategy 2, 0.73) and ulcer-related complications (Strategy 1, 1.18; Strategy 2, 0.23) per 100 patient years. The restricted strategy led to a significantly lower cost per patient treated (Strategy 1, $239; Strategy 2, $831 per year). In the principal analysis, the incremental costs to prevent symptomatic and complicated ulcers were $31,900 and $56,700, respectively. The estimated incremental cost per ulcer avoided was sensitive to the relative protection provided by the safer NSAID and fell dramatically as the patients' ulcer risk was increased above average risk. Conclusion. Unrestricted use of NSAIDs that reduce the risk of symptomatic ulcers has the potential to produce important clinical benefits at incremental cost. The impressive impact of ulcer risk on the incremental cost per ulcer prevented warrants increased attention to risk factor identification when NSAIDs are prescribed.