After rectal surgery, you may need to go to the toilet more often, feel a sudden urge to open your bowels or feel that your bowel has not emptied completely. Sometimes you may need to return to the toilet soon after leaving it. If these changes disrupt daily life, you do not have to accept them as an inevitable consequence of surgery and simply wait; treatment and ways to adapt are available.
These symptoms, which develop after part of the rectum is removed and the bowel is reconnected, are known as low anterior resection syndrome, or LARS. Not everyone develops it, and its severity varies. Symptoms may also appear after a temporary stoma, an opening of the bowel onto the abdominal wall, is closed.
How the bowel works after surgery
The rectum helps store stool until a convenient time to go to the toilet. Removing part of it reduces this storage capacity. The remaining bowel may adapt over time, but it does not immediately take on all the functions of the original rectum.
Surgery can also affect the nerves that sense when the bowel is full and regulate its movement. The function of the anal sphincter, the rings of muscle that hold in wind and stool, may change. Radiotherapy can make tissues less elastic. When several of these effects occur together, you may feel an urgent need to empty your bowels even when there is little stool.
The lower the new bowel join, the greater the likelihood of changes in bowel function often becomes. These symptoms can occur after both open surgery and laparoscopic surgery, which uses a camera through small incisions. In Laparoscopic Surgery for Rectal Cancer, smaller abdominal incisions do not alter the functional effect of removing part of the bowel inside.
Diarrhoea is not the only possible symptom. For one person, leakage may be the main problem; another may pass stool in small amounts and have a prolonged feeling of incomplete emptying. Sometimes these alternate. This is why the same medication and diet are not suitable for everyone.
Which changes should you tell your doctor about?
More detail than “my bowel is not working well” helps guide treatment. You can keep a brief record of your main symptoms:
How many times you go to the toilet during the day and at night.
How long you can hold on when you feel an urgent need to go, and whether you have any leakage.
Whether your stool is loose, firm or passed in small amounts.
Whether you need to return to the toilet after going, and whether you feel you have not emptied completely.
Any connection you notice between food, medication and symptoms.
A diary does more than count toilet visits. It shows how difficult it has become to leave for work in the morning, sleep at night or spend time away from home. Your doctor may also use a short questionnaire to assess symptom severity. The questionnaire does not replace your own account.
Not every new symptom is LARS. Narrowing of the bowel join, infection, radiation-related damage and recurrence of the disease can cause similar changes. If needed, assessment may include a finger examination of the rectum, a camera examination, blood and stool tests or imaging.
What can you expect over the coming months?
Bowel function may be unpredictable in the first few months: good days may be followed by difficult ones again. This pattern does not mean that a new problem has developed each time. However, a clear and sustained deterioration from your previous pattern should be reported to your doctor.
For many people, frequency and urgency decrease over the months. Adaptation can take longer, and some symptoms may persist. It is not possible to give everyone a date by which their previous bowel pattern will return. How much bowel was removed, radiotherapy and individual bowel function all play a part.
You should not have to go through this waiting period without help. Being unable to work, feeling afraid to eat or avoiding leaving home are sufficient reasons to reassess treatment. The aim is not only to reduce daily toilet visits, but also to help you plan your activities more comfortably.
Diet, medication and pelvic floor exercises
Rather than restricting many foods at once, the effects of portion size and meal timing are monitored. Smaller, regular meals help some people. If caffeine, alcohol or very fatty or spicy foods make symptoms worse, reducing them can be tried. There is no need for everyone to avoid all of them.
The type of fibre matters. Soluble fibre in food, which holds water and forms a soft mass, may improve stool consistency. Too much coarse, insoluble fibre can increase bowel frequency and bloating in some patients. A fibre supplement is chosen in consultation with a specialist and introduced gradually. Dietary advice during early recovery may differ from the long-term plan.
When diarrhoea and urgency are the main problems, your doctor may prescribe medication that slows bowel movement, such as loperamide. The same medication can make things worse for someone with constipation or possible narrowing of the bowel. The dose and timing are tailored to the individual. More frequent toilet visits alone are not a reason to start antidiarrhoeal medication on your own.
Pelvic floor exercises aim to improve the strength and timing of the muscles involved in bowel control. A physiotherapist teaches you how to contract them correctly and how to relax them to empty your bowels. Sometimes biofeedback training is used, with a device displaying muscle activity on a screen. The aim is not just to squeeze harder, but to use the muscles at the right time.
Frequent bowel movements can irritate the skin around the anus. Gentle cleaning, careful drying and a suitable barrier cream may help. If the skin is sore or broken, or you have persistent pain, show this during your examination too.
Other treatments when symptoms persist
If initial measures are not enough, transanal irrigation may be offered to selected patients. This involves planned emptying of the lower bowel using a special system that delivers water through the anus. The bowel join is checked first, and a specialist then provides training. This is not a technique to try at home on your own with a large-volume enema.
Another option is to regulate nerve activity using electrical signals from a small device. This treatment, called sacral nerve stimulation, is not suitable for everyone and is usually discussed after the results of earlier approaches have been assessed. If severe, persistent symptoms seriously affect quality of life, a stoma may also be a treatment option for some people.
Increasing abdominal pain with fever, vomiting, inability to pass wind or stool, or heavy bleeding requires urgent medical assessment. New blood in the stool, unexplained weight loss or sustained deterioration should also be reported to your doctor without waiting for your next routine appointment.