Okay thinking about this further it sounds like you might have SIBO.
Excerpt from the article by Amy Myers MD - 10 Signs You Have Small Intestinal Bacterial Overgrowth (SIBO)...
"10 Signs You Have Small Intestinal Bacterial Overgrowth (SIBO)
1. Gas
2. Bloating
3. Diarrhea
4. Abdominal pain or cramping
5. Constipation (much less common than diarrhea)
6. Diagnosis of irritable bowel syndrome or inflammatory bowel disease
7. Food intolerances such as gluten, casein, lactose, fructose and more
8. Chronic illnesses such as fibromyalgia, chronic fatigue syndrome, diabetes, neuromuscular disorders and autoimmune diseases.
9. B12 deficiency as well as other vitamins and minerals
10. Fat malabsorption
How to test for SIBO:
Breath Test: This is the gold standard, however it’s quite cumbersome. Individuals must fast for 12 hours, breathe into a small balloon, ingest a precise amount of sugar, and repeat breath samples every 15 minutes for 3 or more hours. Abnormal breath tests can also signify pancreatic insufficiency and celiac disease.
Organix Dysbiosis Test: This functional medicine lab test the urine for by-products of yeast or bacteria in the small intestine. If your small intestine is housing a yeast or bacterial overgrowth, byproducts will appear in your urine, indicating their presence. This test is much easier for patients and only requires one single urine specimen. This is the test I use most often in my clinic.
Comprehensive Stool Test: This is also a functional medicine lab test looking at the flora of the large intestines. If I see all elevated levels of good bacteria, I suspect SIBO.
History: By listening to the patient’s history and symptoms, I’m often able to make a diagnosis.
How to treat SIBO:
The standard treatment for SIBO is an antibiotic called Xifaxan. Because Xifaxan is not well absorbed throughout the body, it mostly stays in the gut and is very effective against SIBO. The problem with Xifaxan is that most insurance companies have approved it for traveler’s diarrhea, but not for SIBO, so it can be very cost-prohibitive for most people.
In my practice, I place my patients on a diet low in carbohydrates and free of refined flours, sugars and alcohol. I also use a combination of herbs for 30 days, if Xifaxan is too costly. I recommend using our Microb-Clear, which is a blend of magnesium caprylate, berberine, and extracts from tribulus, sweet wormwood, grapefruit , barberry, bearberry, and black walnut. In addition, I follow a 4R program to heal the gut.
Similar to Candida overgrowth, those who are susceptible to SIBO may have reccurrence after treatment. It is advised to adopt a long-term diet that is low in carbohydrates and especially refined carbohydrates.
Should you need additional help, I recommend finding a functional medicine physician in your area."
I was thinking microscopic colitis from that list since you mentioned antibiotics improved symptoms. But now I think about it antibiotics kills off the bacteria that eat the carbs and cause gas build up. Do you notice improvement on a low carb diet?
The good news is you are getting plenty of health benefits from intermittent fasting! :) I love to fast leangains style (16 fast/8 hour eating window). Anyway lol onto the chronic diarrhea which sounds very unpleasant! I posted a few excerpts from the article "Do you have IBS-D, or do you have Habba Syndrome?"...
"That’s what Dr. Saad F Habba, MD,(1) would like to know.
He’s coined the term Habba Syndrome to describe a condition that causes chronic diarrhea and is caused by a faulty gallbladder, and he believes that millions of IBS-D patients have been misdiagnosed and actually have Habba Syndrome."
"Lately, though, Dr Habba has taken his theory even further. In an article published in 2010, he suggested that IBS-D doesn’t exist at all. He studied 303 patients and concluded that 98% of them were suffering from a ‘true clinical entity’ rather than the ‘vague entity’ that is IBS.(2)
Of the 303 patients, he concluded that:
• 41% had Habba Syndrome,
• 23% had diarrhea caused by gallbladder removal,
• 8% lactose intolerance,
• 7% microscopic colitis [Inflammation of the colon visible only using a microsocpe, involving build-up of white blood cells in the bowel lining, and caused, many think, by an abnormal immune response triggered by stressors such as bacteria, medication, or food],
• 4% celiac disease or gluten sensitivity,
• And then a handful of patients had multiple diagnoses, drug-induced bowel problems, infectious colitis or other problems.
In follow-ups, 98% of patients improved significantly when their specific problems were treated appropriately."