bacterial infection
"My doctor had me taking this twice a day for 7 days. I'm on day 5 and have experienced dry mouth (from not wanting to drink), a few horrible headaches (possibly from not being able to drink so dehydration) and periods of fatigue. Today I worked out and got extremely sick which never happens so some advice would be to not do a lot of exercise while on this. It's really not horrible though. Definitely worth the side effects since my symptoms were so unpleasant. My doctor also told me not to drink on it."