I, too have chronic back pain in the right side for 15 + years and have had daily diarrhea the whole time. My new acute pain on the left side has exasperated it over the last 2 months. My doctor agreed with me since she refuses to allow me any real relief with opiods, I should take an Imodium or similar product on really bad days to slow it down. This helps but have gotten so used to it over the years of pain generally I just go 3 or 4 times a day and use it as an excuse to eat everything in sight. I also experience some dehydration from this and so take a large dose (one with every meal, sometimes 4 in a day) of potassium supplement when I notice I am cramping up more. Usually once or twice a week.
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Back-pain connection to diarrhea?.