Nitrofurantoin
"Scary drug for me. I took it for a UTI one month ago and developed a small rash around my ankles and felt "winded" breathing feeling for the first two days, but then was fine. Unfortunately contracted another UTI this month, and took Nitrofurantoin again-- terrifying experience! After the second dose I developed long lasting chills, but my skin felt very hot. Painful cramping in my legs. Red rash all over my thighs. Migraine headache. Extreme fatigue, but could not fall asleep. The worst part was that I eventually could barely breathe, my heart was racing, and had to administer Epipen then head straight for ER. This medication works, but I unfortunately experienced severe side effects and therefore cannot recommend it."