Infusions of Yerbascum lasianthum flowers have been used for hemorrhoids in Turkish folk medicine. In order to evaluate the scientific basis for this practice, in vivo anti-inflammatory and antinociceptive activities of Verbascum lasianthum Boiss. ex Bentham flowers were investigated. A methanolic extract of the flowers was shown to possess significant inhibitory activity in the carrageenan-induced hind paw edema model and in p-benzoquinone-induced writhings in mice. Through bioassay-guided fractionation and isolation procedures eight compounds, 6-O-(4'''-O-trans-p-coumaroyl)-alpha-L-rhamnopyranosylaucubin (1), 6-O-(4'''-O-trans-p-methoxycinnamoyl)-alpha-L-rhamnopyranosylaucubin (2), sinuatol (3), aucubin (4), gemposidic acid (5), catalpol (6), ajugol (7) and ilwensisaponin A (8) were isolated and their structures were elucidated by spectral techniques. An iridoid glucoside, aucubin (4) and a triterpenoid saponin, ilwensisaponin A (8) were found to possess significant antinociceptive and antiinflammatory activities, per os without inducing any apparent acute toxicity or gastric damage. Results of the present study support the continued and expanded utilization of plants employed in Turkish folk medicine. (c) 2006 Elsevier Ireland Ltd. All rights reserved.