I've had long-running gut issues, about 25 years or more of IBS-D type symptoms. I was recently diagnosed with Chronic Active EBV and Lyme disease. After the conclusion of a 30-day course of Doxycycline, my gut habit has improved. I feel better, too. I suspect that somehow my pancreas was having an issue. (My stool no longer floats.) If it was sick, it will probably take some time to recover, but so far so good.