bladder infection
"After having six UTIs in about 5 months, my urogyn put me on 100 mg. of Macrobid (one every night).  After ten solid months of it, I spent 2-1/2 days in the hospital:  thought I was having a heart attack!  Turned out it was a pulmonary problem.  Heavy pressure in the chest, shortness of breath and tingling around the lips.  Going back and researching Macrobid, I found out that indeed, long term usage can cause pulmonary problems.  I do think if works for short term usage."