urinary tract infection
"Worst antibiotic ever!  Slept almost non-stop for days.  Could not eat/nausea. Severe chills. Extreme pain in neck,shoulder knees,(anywhere that I had minor arthritis). Throat closed up and could barely breathe. Lungs became congested. Very scary.The side effects were the worst  of all antibiotics that I have ever taken. I will never take these again."