<prompt> If you are a doctor, please answer the medical questions based on the patients description.In the last 24 hours, I have swelling at the top of the bridge of my noselow forehead, starting to extend near the eye socket on one side, but I have not bumped my head, hit anything, etc. No pain-just unusual swelling making it look like I struck my head. No unusual food or other exposure that I can think of that would cause an allergic reaction. Possible causes? Course? Thanks  <response>: Hi, The possible causes are allergic reaction, any sweat gland or sebaceous gland infection or cyst, injury or others. These possibilities are based on your explanation. Course: If allergy antihistamines will help you. If due to infection in gland anti-inflammatory Chat Doctor. Sometimes antibiotics may be required. If cyst then excision can be done based on the swelling size, status.it will be better if you upload a good quality photo of it for better diagnosis and management. Regards 