Overflow diarrhoea

A firm stool mass can remain in the rectum or bowel while softer liquid stool moves around it. You may notice watery leakage, small amounts of stool, abdominal swelling, cramping, straining, or a feeling that you have not emptied fully. This can be mistaken for an ordinary diarrhoeal illness.

Constipation can follow reduced movement, low fluid intake, changes in routine, or medicines. Other bowel conditions, including irritable bowel syndrome, Crohn's disease, coeliac disease, food intolerance, gastroenteritis, food poisoning, giardiasis, or an overactive thyroid, may cause diarrhoea but do not all cause overflow.

Arrange medical advice if watery leakage occurs with constipation, pain, swelling, or repeated incomplete bowel movements. A clinician may examine your abdomen and rectum, review medicines, and recommend a bowel-clearing plan followed by steps that keep stools soft. Do not take anti-diarrhoeal medicine when blockage is possible unless a clinician advises it.

Drink fluids unless you have been told to restrict them, move gently if able, and respond to the urge to open your bowels. Use laxatives only as directed, particularly if you have severe pain, vomiting, or a long-standing bowel problem.

Seek urgent help for severe or worsening abdominal pain, a hard swollen abdomen, repeated vomiting, inability to pass stool or gas, blood or black stool, fever with marked illness, or signs of dehydration such as faintness and very little urine. Children, older adults, and people with significant bowel disease may need earlier assessment.

Ask whether your symptoms suggest overflow, which medicines or conditions could be contributing, how to clear the bowel safely, and what changes should lead you to seek urgent care.