Faecal impaction is a medical term that describes a type of constipation where hard stool builds up in the large bowel or rectum and can no longer pass out of the body naturally. The word comes from Greek: "kopros" means stool, and "stasis" means standstill, so it describes a state where bowel movements have quite literally come to a halt.
How does faecal impaction develop?
Faecal impaction often develops as a result of long-term constipation, which doctors also call obstipation. The stool stays in the bowel for an unusually long time, drawing more and more water out of the body as it does so, and gradually becoming very hard. Eventually, a solid "stool plug" can form in the large bowel or just before the anus, blocking the natural movement of stool. Older people, those who are confined to bed, or people with certain underlying conditions are particularly affected.
Sometimes faecal impaction is caused by not drinking enough fluids, eating a diet low in fibre, or not getting enough exercise. Certain medicines, such as strong painkillers (for example opiates), can slow down bowel activity so much that this kind of blockage occurs. In rare cases, serious conditions such as tumours or neurological disorders are behind it.
How can faecal impaction be recognised?
Typical symptoms include no bowel movements for several days, an uncomfortable feeling of fullness in the abdomen, pain or pressure in the lower abdomen, and sometimes nausea. A bloated stomach, loss of appetite, or the feeling of not being able to empty the bowel properly are also common signs. In some cases, something called overflow diarrhoea can occur: loose stool passes around the hard plug, leading to repeated, seemingly watery diarrhoea. This is a sign that a backlog has already built up inside the bowel.
Is faecal impaction dangerous?
The idea of stool building up inside the body can understandably be worrying. Many people wonder whether it can become dangerous or even turn into an emergency. Faecal impaction should indeed be taken seriously, because if left untreated it can lead to complications. As the stool plug grows larger, the pressure inside the bowel increases. This can damage the bowel wall, cause inflammation, or in the worst case lead to a bowel obstruction. In very rare cases, the bowel wall can even rupture (perforate), which is a life-threatening situation.
However, faecal impaction can usually be treated well if it is caught early. Anyone who has had no bowel movement for several days, is experiencing strong abdominal pain, or notices other unusual symptoms should seek medical advice.
What helps with faecal impaction?
Treatment depends on how severe the blockage already is. In mild cases, it may be enough to change your diet, drink more fluids, and move around more. A diet rich in fibre is particularly helpful for long-term constipation, and this includes fruit, vegetables, and wholegrain products. Going to the toilet regularly and drinking enough fluids also supports digestion.
If a stool plug has already formed and is causing symptoms, enemas or bowel washouts are often used to flush the bowel from the outside and relieve the blockage. In some cases, special suppositories or laxatives are used. Very hard or large masses of stool sometimes need to be removed by a doctor. This is done carefully and under medical supervision.
It is important to find out what is causing the faecal impaction. If, for example, neurological conditions, tumours, or side effects of medicines are the underlying cause, treatment needs to be tailored to the individual.
What can help to prevent it?
Anyone who is prone to constipation or has had faecal impaction before should pay attention to keeping their digestion healthy. Getting enough exercise, drinking plenty of fluids, and eating a balanced diet with plenty of fibre are the most important steps. It is also important not to delay going to the toilet for too long. For people who are confined to bed for a long period, or who are taking certain medicines, it may be worth speaking with a doctor to put together an individual plan for prevention.
More about constipation and how a tendency towards constipation can present itself can be found in a separate article.
When should medical advice be sought?
The feeling of being unable to have a bowel movement can be very distressing. If abdominal pain, nausea, vomiting, or fever are also present, it is important not to wait too long. For older people, children, or those with serious existing health conditions, a medical assessment should be sought early. The sooner treatment begins, the better complications can be avoided.
Faecal impaction is uncomfortable and can in some cases become dangerous, but with the right support and treatment, most people can be helped very effectively.
Scientific sources
Serrano Falcón B, Barceló López M, Mateos Muñoz B, Álvarez Sánchez A, Rey E. Fecal impaction: a systematic review of its medical complications. BMC Geriatr. 2016;16:4. doi:10.1186/s12877-015-0162-5
Bharucha AE, Dorn SD, Lembo A, Pressman A. American Gastroenterological Association medical position statement on constipation. Gastroenterology. 2013;144(1):211–217. doi:10.1053/j.gastro.2012.10.029
Lembo A, Camilleri M. Chronic constipation. N Engl J Med. 2003;349(14):1360–1368. doi:10.1056/NEJMra020995
