Introduction/Aims: irritable bowel syndrome (IBS) is a common gastrointestinal disorder in which patients have chronic abdominal pain associated with an alteration in bowel habits. We have recently shown that IBS patients have cutaneous hyperalgesia, suggestive of a central hypersensitivity mechanism similar to fibromyalgia (FM) (Verue et al., 2001). The aim of the current study was, to compare magnitude and spatial distribution of cutaneous thermal hyperalgesia in patients with IBS, IBS + FM, and healthy controls. Methods: Twenty patients (9 women, 11 men)(mean age 34.5 +_ 2.5 years) with IBS, 12 patients (11 women, I man) (mean age 475 _+ 86) with IBS + FM, and 17 control subjects (13 women, 4 men) (mean age 33.8 _+ 9.4) rated pain intensity and unpleasantness to thermal stimulation (45 and 47~ of the hand and foot on a 0-10, M-VAS scale. Sex differences among subjects was compared and did not show any significant effect, so sexes were combined for final analyses Results: IBS + FM patients reported higher foot pain scores than either the controls or IBS patients at both temperatures (45, 47~ The IBS group reported higher foot pare scores than the control group at both levels (45, 47~ of stimulation (p