I have developped swelling of my upper lip the last 12 hours. It first started with feeling of Itching around the left side of my upper lip, which I started rubbing and biting. I first thought it would be the occasional rash on my upper lip. It started with showing swelling and it was blown to complete swelling on my upper lip in less than three hours. I went to deep sleep and the swelling has not decreased after12 hours. the swelling has not caused me any pain but I am feeling stiffness. I had similar swelling four months ago involving my both lips; started same way with my lower lip and persisted for about 24 hours and restarted with my upper lip the next day to stay for about the same time. This current swelling did not involve my lower lip yet. The swelling is so big that it affected my facial look. I had never experienced this untill the first one four months ago, with which acute fever and flu were associated. I have no sickness associated with this current one. I want to know the possible causes of the pattern of this lip swelling.