In most cases, allergies are little more than annoying and inconvenient. They may cause us to break out in an itchy rash, sneeze constantly or get sinusitis. But some allergic reactions are much more serious, requiring immediate medical attention. Such a severe reaction is known as anaphylaxis, or more commonly, anaphylactic shock.

Almost anything that a person is allergic to can cause anaphylactic shock. Some of the most common culprits include:

• Bee stings and insect bites
• Medications
• Foods, particularly shellfish, nuts, fruit, wheat, milk, eggs and soy
• Latex
• Blood used in a transfusion

In most cases, the initial exposure to the allergen does not cause a reaction. But the immune system recognizes it as a foreign substance, and the next time the allergy sufferer comes into contact with the allergen, it reacts quickly. The body begins to produce the antibody Immunoglobulin E (IgE), which triggers the release of histamines. The histamines have an adverse effect on the body's tissues and organs, resulting in a severe allergic reaction.

Anaphylactic shock produces a number of dangerous symptoms. Swelling and spasms in the airway can cause difficulty breathing. Blood pressure may drop quickly, causing loss of consciousness. The victim may become confused and disoriented. And in the most severe cases, the heart may stop. Less serious symptoms include hives, swelling of the face, hands and feet, nasal congestion, nausea and diarrhea.

How to Treat Anaphylactic Shock

One of the most dangerous aspects of anaphylactic shock is how quickly it can happen. In some cases the reaction begins slowly or is delayed for a few minutes to a few hours. But most of the time, serious symptoms appear with little or no warning. For this reason, any signs of an allergic reaction should be taken very seriously. Patients showing any sign of anaphylaxis should be taken to the emergency room immediately. In the case of rapid swelling, dizziness or trouble breathing, someone should call 911.

If you have never experienced anaphylactic shock before, you may not have the medications needed to treat it. If you have, however, it's important to have them on hand in case of emergency. Patients with anaphylactic shock should avoid further exposure to the allergen and take an antihistamine such as Benadryl if possible. Those who have experienced trouble breathing should use a prescription inhaler. An EpiPen should also be used if available. The EpiPen provides a dose of epinephrine, a drug that can quickly reverse the most dangerous symptoms of anaphylactic shock.

Anaphylactic shock can be life threatening. Those who have experienced it should be very careful to try to avoid the allergens that triggered it. However, sometimes contact with allergens is unavoidable. In the event of exposure, being prepared can save your life.