Anaphylaxis
What is it?
Anaphylaxis is a severe, potentially life-threatening allergic response. Though symptoms vary, anaphylaxis is most often characterized by tongue swelling, hives, vomiting, and shock due to lowered blood pressure.
Symptoms
Symptoms may occur immediately after exposure to the allergen (the substance to which the individual is allergic to), or may be delayed for as much as an hour. An individual is highly likely to be experiencing anaphylaxis if any one of the following occurs within minutes to hours after exposure to allergen:
- The individual was exposed to known allergen and experiences reduced blood pressure (as indicated by paleness, weak pulse or loss of consciousness).
- The individual was exposed to a suspected allergen and two or more of the following symptoms occur:
- Difficulty breathing
- Reduced blood pressure
- Skin symptoms and/or swollen lips
- Gastrointestinal symptoms (vomiting, diarrhea, or cramping)
- The individual has symptoms related to the skin, nose, mouth or gastrointestinal tract and difficulty breathing or reduced blood pressure (as indicated by paleness, weak pulse or loss of consciousness).
Causes
Anaphylaxis can occur in response to any allergen. Most common causes include:
- Drug allergies: some drugs, such as morphine and x-ray dye may cause an anaphylactic-like reaction.
- Food allergies: Peanuts, tree nuts, fish and crustacean are the most common foods to cause such severe allergic responses.
- Insect bites/stings: Substances such as bee sting venom may trigger anaphylaxis.
Diagnosis
A diagnosis of anaphylaxis is based on the presence of the symptoms listed above.
If a patient suspects that they are experiencing an anaphylactic reaction, they should seek emergency care immediately. An EpiPen, which injects epinephrine, should be administered to the outer thigh if the sufferer has a history of such reactions, or under the guidance of a health-care provider. Medical attention should still be sought immediately after symptoms subside.
sources: http://www.foodallergy.org/anaphylaxis
http://www.nlm.nih.gov/medlineplus/ency/article/000844.htm
http://www.webmd.com/allergies/guide/anaphylaxis