What Causes Diarrhea After Every Meal?

Question: Hello, I first started having problems in 2008 with diarrhea once a week. worsened from 2012-14, and again from 2017... Currently it is every day after most meals, sometimes every 15 minutes for a few hours with cramping. I usually have about 4-5 movements per day, mostly loose stool. It usually can be prevented with lomotil and 6 welchol, but returns the next day.

My GI doctor thinks I have IBS-D (2 colonoscopies came up negative for colitis / crohn's / celiac), and we've tried almost every medicine available for diarrhea without much success. (Welchol works somewhat, but I still have about 7 bowel movements per day with loose stool, sometimes 15 minutes after eating). Viberzi was great until had sphincter of oddi spasm and discontinued it.

Today my family doctor recommended taking Octreotide, however my wife and parents are worried about the side effects since it's usually for cancer. Do you think it would be dangerous to try for a week? I'm having so much inconvenience from diarrhea that I'm willing to almost try anything, but my wife (an RN) won’t give me the injection unless she thinks it’s safe to use. Also, do you think I could be in the early stages of an inflammatory bowel disease? (I’m switching GI specialists but it’ll be a few months until the appointment).

Thank you,
Philip

Hello Dr. Klerida,

Thank you for your kind and detailed answer!  Is there a type of food intolerance test that you recommend?  I had food allergy prick and blood tests in Korea, all came back negative.  Only positive was a mild reaction to a wheat sensitivity test in 2012.  However, my GI doctor told me that it was a false positive and to keep eating wheat after colonoscopy in 2014.  (I didn't eat wheat for those two years but still had similar symptoms.)

I tried rifaximin in Korea and the US 2 times.  The last time was this Christmas while I was on probiotics.  Each time I couldn't tell a difference.  I also couldn't tell any improvement with bentyl.

Thank you for letting me know about Octreotide.  I understand that it might not be effective and is not used for IBS, however, I'm afraid I don't have much treatment options left.  From a safety perspective (and I understand that there's always risks with medicine), do you think it would be harmful or cause any permanent damage taking it for a week at a low dose?  Along as there is not a great risk of damaging something permanently, I'd like to give it a try.  

Thank you for your help and advice!
Philip