Restenosis is the major adverse effect of coronary stent implantation. Drug-eluting stent has markedly reduced restenosis as compared with bare-metal stent, but restenosis is still the main cause of repeat coronary intervention after drug-eluting stent implantation. After coronary stent implantation, inflammatory reaction occurs in vessel wall and vascular smooth muscle cells proliferate. Celecoxib is well known to have anti-proliferative effect as well as anti-inflammatory effect, and safety of this drug is well-established. Celecoxib use for 6 month after paclitaxel-eluting stent implantation significantly reduced neointimal growth and repeat intervention without increase in adverse effect. Because inflammatory reaction seems to occur in very early period after vessel injury, reduced use of celecoxib may also be effective.