Weâ??ve all experienced it at one time or a**ther: abdominal pain and cramping â?? and then diarrhoea. For most of us, acute diarrhoea, which lasts for less than two weeks, is an occasional event possibly caused by a virus, eating something that didnâ??t agree with us or even a reaction to stress. But chronic diarrhoea, too, affects many people. Chronic diarrhoea could last for months and be caused by illness, medication side effects, or food intolerances.