Nitrofurantoin
"Took one pill and it felt like a miracle. Was put on a dose of 1 tablet twice daily for 3 days. By the 5th tablet I was feeling flu like symptoms and dizziness. Not sure if I’m just feeling under the weather or it’s a side effect of taking this medication. Urine has also been bright yellow as many others have also stated. 
I would rather have this flu like symptom than feeling like I’m urinaring out razor blades. It definitely worked quickly and that worked for me."