I had been on metformin for years, before last Christmas I contracted salmonella poisoning, never did quite recover properly until just recently, back in January I had HBc levels of 18.9, doctor increased my metformin to 1500 grams per day plus glipizide, I continued with diarrea for another 7 months! tests, some not very pleasant because they suspected bowel cancer, 2 weeks ago saw the Endocrinologist who immediately stopped the metformin and I feel so much better, however, have to go on insulin next week but am beginning to feel positive about it