Nitrofurantoin
"I was prescribed macrobid for a 3 day course, 2 doses a day. The first day I seemed to be getting better, but then I woke up at 4:15am the morning of the second day with chest pains. Throughout the day I suffered from headaches, chest pains, muscle and joint aches, nausea, dizziness, fever and chills. Now on the third day, and though I'm not feeling as ill anymore, I'm still dealing with chest, back and stomach pains. Can't even tell if treating the UTI because I've been in so much pain. Worst experience I've ever had with antibiotics - would definitely never use macrobid again!"