Background: It has been reported that stent restenosis is related to allergic reaction to metallic component of the stent. Therefore, we wanted to evaluate prevalence of allergic reaction and its impact on stent restenosis in carbon coated stents (Arthos Inert stent and Technic stent). Methods: From June 2003 to July 2003, total 87 patients (43 carbon coated and 44 non-carbon coated patients) were enrolled in the study. Allergic patch test was conducted to the 4 components (potassium dichromate, nickel sulfate, manganese chloride and molybdenum). Allergic reaction was interpreted by 2 different dermatologists at 48 and 72 hours after the patch attachment. Results: Positivity of allergic reaction was observed in 22 in potassium, 18 in nickel, 33 in maganese and 49 in totally. However, the restenosis rate was not different between the positve and negative allergic test patients (26 vs 31%, p=0.66). The data of carbon coated and non-carbon coated stents were listed in the table. Conclusion: Carbon coated stent did not seem to influence to reduce allergic reaction and stent restenosis.