None of these are miracles, but they have helped me. I still have issues with long BM times and soft, fragmented stools but not as bad as before.
Get some Pentasa from your doctor. I have titrated the best dose for me to 250 mg and use it when having a bad day, along with Imodium if needed. It helps a lot to settle down excessive cramping and urgency. Some people can take Pentasa long-term. I tried, but it caused pain near the gallbladder after about a week of use. But for a day or two, it was fine and really helped by reducing inflammation in the gut.
Be careful when using constipating drugs such as Imodium. If they work too well, they cause the gut to back up and then it will get angry and empty out eventually, resulting in a very bad day or multiple days. Cycling back and forth between bad LARS and calm days isn't a good situation for me so I save the Imodium for situations where I need to be out of the house or symptoms that are especially bad.
Sugar alcohols are present in a lot of processed foods and some fruits. They can cause big problems. Look for sorbitol, mannitol, maltitol, erythritol, and xylitol on labels. Avoid them. Stone fruits such as peaches, plums, cherries, and nectarines have it, also sweeter kinds of apples and pears, but it can vary by variety. I've found some I can eat, others, no way. Look up the "FODMAP diet" for ideas on how to limit these.
After chemo, the gut can develop allergies to some foods. I found I can't eat quinoa anymore, sweet pickled red peppers, or chipotle peppers. It can take a while to figure out by elimination of foods then adding back one at a time.
SIBO (small intestine bacterial overgrowth) is a condition where gut bacteria colonize the small intestine. It revs up LARS like crazy. You can get a breath test for it you can do at home, send samples to a lab and they mail you the result. But it's usually not covered by insurance. It can be speculatively treated with herbals that aren't too expensive and if symptoms improve you can take the herbals every few months if symptoms return. SIBO can't be cured, it usually recurs after several months. But repeated treatments bring it back under control. An antibiotic treatment is also available but it can be pricey in the US. See https://journals.sagepub.com/doi/epdf/1 ... j.2014.019
for more details on the herbal treatments. I ended up using Candibactin AR and Candibactin BR every 4-6 months, and it helps quite a bit.
Some drugs can aggravate LARS. I found that ED drugs in the PDE-5 class (Cialis, Viagra, etc.) are murder on the gut. Also, an eyedrop that ophthalmologists use to dilate the eyes called Tropicamide does it too. If taking medications, look at side effect lists for things like "upset stomach" or diarrhea. Try stopping or changing them to see if it helps.
When LARS flares, it can abrade the anal area. The pain and irritation causes a cascade of cramping that makes the gut empty out, exacerbating the irritation, and worsening things considerably. Foods with seeds or chunky fiber that don't digest such as blackberries or nuts act like sandpaper on the anal tissue. I've had to limit these foods or do things like puree blackberries and strain out the seeds before putting them into smoothies or adding to oatmeal.
High-volume tap water enemas give me a break. I've heard reports that low-volume enemas with an empty Fleet enema bottle can wash out the fragments and stop the cramping for some people. It's not that helpful for me because once the anal tissue gets inflamed, the enema tip causes more pain even with lots of lube. I had radiation in that area and it's the reason for the sensitivity. Others with higher tumors that didn't get radiation near the anus might benefit more.
I also had pelvic floor physical therapy and MRI defecography to rule out any other physical issues. They helped a bit but again were not miracles. Worth a try, especially if you have insurance that will cover it. Abdominal exercises and walking or other aerobic exercises help the gut pass stool along more quickly and regularly. They take time but do give more predictability to when I need to go.
Rant: Oncologists have no idea that the rectum is a VITAL ORGAN. it shouldn't be ripped out and thought of as something like an appendix or tonsils. When cancer patients lose the rectum, it has many social and quality-of-life consequences. So much of our socializing revolves around dining. Rectal resection can be very isolating. I've lost lots of friends due to the dietary and time restrictions, and finding accepting new ones has been difficult. Any newly diagnosed cancer patients reading this need to discuss "organ preservation" with your oncology team. Rectal resection should be a last resort, not the default treatment for people with rectal cancer.