My husband was bitten by what the doctor thinks was a spider, last Sunday ... his arm , chest, hand , all were swollen and breathing deeply was difficult. A trip to emerg and two trips to the doctor last week and told to just wait. Now there is a definite blue / purple line working it s way down from his shoulder to middle of bicep ... the arm and hand are still very, very swollen. It is a week later to the day. How long should this last? Should we be going back to emerg?