What causes sudden swelling and thickening of the upper lip?

Sudden swelling of the upper lip can be caused by various factors, including allergic reactions, oral diseases, insect bites, or trauma. Allergy is one of the most common causes and may be triggered by foods, medications, cosmetics, or environmental substances. Eating certain foods that may cause allergies, such as nuts or seafood, or using new toothpaste or lipstick could be responsible. Intraoral diseases such as gingivitis or mouth ulcers may also lead to localized swelling.

If accompanied by itching, redness, or other allergic symptoms, it could indicate an allergic reaction. If there is pain or pus discharge, an infection may be present. Insect bites, such as mosquito bites, can also cause localized swelling. Minor bumps or cuts may lead to temporary swelling.

It is recommended to monitor for the appearance of other symptoms and seek medical attention promptly. A doctor may suggest using anti-allergy medications such as over-the-counter antihistamines or provide other treatments depending on the situation. If the swelling persists, pain worsens, or emergency symptoms such as difficulty breathing occur, immediate medical attention is required.