Suggest Treatment For The Itching And Swelling In My Lips

I have had on two occassions, without proper diagnosis, itching primarily on upper lip with very tiny flesh colored bumps. On one occassion my lips swelled when eating. I have not eaten anything I am known to be allegic to, no breathing difficulties and cannot find resolution form the bumps when taking benadryl, which reduced the swelling on that one occassion. These seem to be bothered when eating anything and often burn. What causes, other than allergies, could produce this type of response?