As expected, higher plasma ACTH levels in patients with IBS were associated with higher levels of serum cortisol (β = .94, P < .001); we found a similar association with plasma adrenaline levels (β = .972, P < .001) during strong distention in patients with IBS who were administered saline, and plasma ACTH levels in patients with IBS patients who were administered CRH (cortisol: β = .711, P < .001; adrenaline: β = .496, P < .001). This evidence concerns the gene POMC and irritable bowel syndrome.