sinusitis
"I'd taken Amoxil before and had no reaction to it, but apparently you can develop an allergic reaction to this medicine. The doctor prescribed this along with a new allergy medicine so it took about three days before the allergy medicine couldn't fight off the reaction that I (up until that point) didn't realize I was having to Amoxil.  It started with swollen spots in the back of my throat before I went to bed.  My roommates mother is a nurse and told me to take extra Benadryl which is probably what saved me because by 4am I had to go to the emergency room because my throat was swelling closed and I only had a small airway left.  The good thing was that this reaction took place over several hours and could EASILY be treated."