Oh my gosh, both boys pee so much more when they are on antibiotics. We have never done antibiotics, but any oral antibiotic they take, seems to make them go more. I have to make sure to put night night pull-ups on them at the last minute before they go to bed, or they will soak through them.
I don't know why this occurs, but it is definitely related to the antibiotics.
blessings,
missa