Changes in myoelectrical activity in the irritable colon syndrome with prolonged treatment.

Twenty patients with established irritable colon syndrome were studied at presentation and following a mean period of 14.3 months of bran treatment. An abnormal myoelectrical activity consisting of a high incidence of 3 c/m slow-wave electrical activity was recognised in the rectosigmoid and confirmed by objective automated frequency analysis. After the period of prolonged treatment, the high 3 c/m slow-wave activity persisted, but the incidence of 6--9 c/m activity increased. This was associated with an improved stool weight and transit time in patients with predominant constipation but no alteration in patients with predominant diarrhoea.