urinary tract infection
"I took Nitrofurantoin for 7 days and while it cleared the UTI I have never felt so ill on it.  This was two and a half weeks ago and I suspect the side effects are still around but not as severe. Headaches, flu like feeling and ringing in my ears and chest congestion.  I don't feel back to normal.  Does anyone know how long it will take to get back to normal? I'm in the UK."