An allergic outbreak involving the lips is manifestation of angioedema. Angioedema is a kind of allergy that affects subcutaneous tissue, the layer of tissue below the skin. Angioedema may occur alone or be part of a reaction that involves the entire body. While patients with mild angioedema can be treated with medications, those with severe reactions may need emergency medical treatment.
Causes
In allergies, the immune system, which normally serves to protect the body against infections, reacts against a normally harmless substance. Common allergic triggers include insect bites, medications, pollen and food. These agents can activate the immune response in susceptible individuals. Histamine, a chemical secreted by mast cells, causes blood vessels to become dilated and leaky; this is responsible for many of the symptoms of angioedema.
Symptoms
Angioedema causes swelling of the lips. It frequently also involves the eyes and cheeks. In some cases, an individual's hands, feet or genitals may be involved. The sites of involvement rapidly become swollen and puffy. Angioedema often occurs with hives, which is an allergic reaction that occurs in the skin. Hives are characterized by the formation of red, itchy welts in the skin. Serious allergic reactions can cause anaphylaxis, which leads to breathlessness, wheezing, a fall in blood pressure and an irregular heart rate.
Treatment
Mild cases of angioedema can be treated with antihistamines, such as cetirizine or loratadine. Individuals who develop severe allergic reactions involving the lips need to go to an emergency room to get treatment. The most important treatment is epinephrine, given as an injection. Epinephrine causes blood vessels to narrow and dilates the airways; this relieves many of the symptoms of angioedema. Oral steroids are useful in these severe reactions as they can reduce the immune response.
Prevention
The most important way to prevent angioedema is to avoid the irritating substance. If it is unclear what might have caused the reaction, skin testing can be done. In this, small amounts of irritants can be injected into the skin. Formation of swelling and redness at one of these sites is indicative of an allergic reaction. In some people, injection of even a small quantity of allergen may trigger a response; because of this, testing always should be done in a medical facility. Patients with severe allergies should carry an injectable form of epinephrine with them at all times in the event of a severe reaction.
References
- "Kumar and Clark's Clinical Medicine"; Praveen Kumar, et al.; 2009
- PubMed Health: Angioedema
- MayoClinic.com: Hives and Angioedema
