R-flurbiprofen, a nonsteroidal anti-inflammatory drug derivative, has been shown to inhibit colonic adenoma formation in mice. We investigated the effects of R-flurbiprofen on cell proliferation and apoptosis in pituitary adenoma cell lines. GH4C1 rat pituitary cell line cultures and low-passage human primary pituitary cell cultures were treated with varying concentrations of R-flurbiprofen (0.1-1.0 mM). R-flurbiprofen inhibited cell proliferation in a dose-dependent fashion. A terminal deoxynucleotidyl transferase dUTP nick end labeling assay and chromatin condensation/dead cell apoptosis assay demonstrated induction of apoptosis at higher concentrations of R-flurbiprofen. R-flurbiprofen decreases cell proliferation and induces apoptosis in pituitary adenoma cells in vitro. This may be a potential therapy in the management of pituitary adenoma.