urinary tract infection
"This drug is going on my "Do Not Prescribe" list.  After a day and a half on it, the fatigue was so bad I could barely function.  No one claimed to know anything about this side effect, but when I looked it up I kept seeing it happening to users again and again.  It helped my UTI, but I couldn't get off the couch.  I phoned my doctor and was switched to Cipro.  After skipping my evening dose of Macrobid and taking Cipro instead, I felt almost normal the next day.  Be very, very cautious about using this drug."