The most serious allergic reactions involve the entire body. An anaphylactic reaction can be triggered by exposure to any allergen through inhalation, ingestion, injection, or skin contact. It is a severe, rapidly developing, fatal allergic reaction. An estimated 1.21% to 15.04% of the American population are at risk for anaphylaxis and causes around 400-800 deaths annually. If left untreated, the condition may lead to shock or even death.
Mechanism of the Reaction
The most severe of allergic reaction is anaphylaxis. Upon the initial exposure of a person to an allergen, the body automatically produces antibodies that are specifically matched to the foreign agents. These antibodies called IgE antibodies bind to the surface of the mast cell found in connective tissues and a type of white blood cell called basophils.
Anaphylaxis is mediated when this foreign antigen (allergen) is re-introduced into the body, and binds to a specific IgE. Within minutes or even seconds, this triggers the release of histamine and other chemicals that result into smooth muscle spasms, narrowing of the airway, edema, and eventually circulatory collapse.
Anaphylaxis is triggered by various allergens that a person may be sensitive to. Common causes are:
* Foods— nuts, shellfish, fish, milk, eggs, soy, wheat
* Medications— antibiotics, allopurinol, iodine-based contrast agents, anesthesia, vaccines, hormones, aspirin, non-steroidal anti-inflammatory drugs
* Other biologic agents— tetanus antitoxin, snake venom antitoxin, antigens for skin testing
* Insect stings— bees, wasps, hornets, ants
* Latex—medical and nonmedical paraphernalia
The time elapsed upon the exposure to the antigen to the onset of symptoms would help indicate the severity of the reaction. Mild reactions range from itching, sneezing, tearing of the eyes, to nasal congestion and puffiness around the eyes than begins within the first 2 hours of exposure to the antigen, while moderate reactions include generalized flushing and feeling of warmth. Severe reactions occur abruptly and rapidly progresses to swelling of the throat that could possibly lead to the constriction of airways or even blockage. Cardiac arrest and coma may follow.
What Your Doctor Can Do For You
Severe allergic reaction may take place rapidly, thus, it is important to seek professional help. Signs and symptoms are evaluated by the physician before rendering appropriate intervention. The sooner the condition is diagnosed, the better the prognosis. In addition, the patient may need to be tested for allergies, and be taken some blood samples to rule out any other condition.
Emergency care is needed in cases of anaphylaxis. The severity is first evaluated, followed by the respiratory and cardiac status. In cases of cardiac arrest, cardiopulmonary resuscitation is started. Oxygen is administered in high concentrations to prevent brain damage. And intubation may further be instituted as necessary.
Epinephrine, the primary drug for anaphylaxis, is administered in very low concentrations into the subcutaneous tissue of the upper thigh. EpiPen is a handy autoinjector of premeasured doses of epinephrine. Antihistamines and corticosteroids may be given to relieve symptoms of inflammation and also to prevent recurrence. Bronchodilators like aminophylline helps improve the airway function. Further treatment includes drugs that improve the vascular status. The patient is closely monitored on the first 12 hours.
What You Can Do
Strict avoidance of potential allergens is an important preventive measure. If avoidance is impossible, an emergency kit containing epinephrine should always be available. Once you suspect an allergic reaction with the signs mentioned, call 911 for medical help. Assess the breathing and cardiac condition of the patient, and administer CPR. People with recognized allergy reactions should wear some form of identification such as a Medic Alert bracelet. Those who’ve had mild to moderate reactions should also seek medical help. If you don’t, you may be missing out on a treatment that may of great help and perhaps save your life.
