Hi my son who is 29 y /o called me yesterday telling me he had noticed blood in urine all day yesterday 07/31/2012 and at 1am called back and he stated he was passing clots too. He stated he is in no pain, has no fever, he stated he was recently fighting a bad tooth and was on antibiotics for that. Because this really scared him I told him I would not think it life threatening but advised him to see his Dr. today. I looked online and realized there are hundreds of reasons for sudden onset of blood in urine. What I m wondering is if there was n infection in the tooth could that have affected him with a bladder infection or UTI , I am unsure and just wondering if it is related? Also could taking an antibiotic cause sudden onset of the bleeding? Thank you, wondering mom. Neena