I am 30+, few years back flaura and fauna in my intestine was disturbed and I had lot of stomach issues and got irritable bowel syndrome. Done lot of testing - ultrasound, stool etc. No issue is noticed in any testing. Now - what I noticed is my stool diameter is hardly 1 cm normally. But whenever I take any anti biotics for any reason (eg-throat issue) the stool/bowel width increases to 2 cm or more. If there a issue here I need to worry and if so how to proceed?