I have a urinary tract infection for which was cultured and my doctor placed me on Metronidazole. After the first day of taking two tablets I woke up the next morning with a bright red face abs some facial swelling. I ended up in the ER as it is Saturday and was prescribed tinindazole 500 mg. My pharmacy has filled this prescription under objection because the two drugs are closely related. I tried to talk to the ER MD supervisor to see what I should do and was treated rather rudely and told this was not a problem. I have almost died from allergic reactions in the past because of sea food allergies and while I know this is. Not the same,to me it is.