Overview Vascular Endothelial Protection Effects of Dextromethorphan Status: Completed Trial end date: 2005-12-01 Target enrollment: Participant gender: Summary To test the hypothesis that DM could have anti-inflammatory effect and thus achieve vascular protection effect on heavy smokers. Phase: Phase 4 Details Lead Sponsor: National Cheng-Kung University HospitalTreatments: Dextromethorphan