My 16-year-old plays jazz and wind ensemble and is experiencing -- for the second time this year -- swelling of the lips and tongue. Previously after laying off for a while, the swelling went down and he resumed playing, losing his chops. It is a painful condition. Benadryl seems to have lessened the swelling. He uses a plated mouthpiece, but it's possible there are tiny nicks on it that may expose him to brass. There seem to be non-brass mouthpieces but they seem to affect the sound negatively. If you have suggestions, advice on either the cause of the swollen lips/tongue and/or information on non-allergenic mouthpieces, that would be immensely appreciated.