Sulfamethoxazole / trimethoprim
"Started taking Cipro for a bladder infection but had some bad side effects in the tendon in my right hand. Went back to the Dr. And he gave me Bactrim(Septra).   I took it for 3 days in total before I had to stop. The symptoms literally made me feel like I was dying. I had a really foggy head, headaches, dizziness, I almost passed out one day. I got zero sleep the whole time I was on it. My joints hurt in the night, my skin got really itchy and developed a rash, I also developed extreme anxiety and I felt like I was having a heart attack with the palpitations. I was close to panic attack  that's when I said enough is enough. I've never had a reaction like that and I have trouble remembering those days.   It was a blur of pain and confusion."