Though 250-500 bee stings may be needed to kill a healthy adult, for those allergic to bee stings, only one sting can kill. Such a severe allergic reaction is known as anaphylaxis or anaphylactic shock.
Anaphylaxis typically comes on within minutes of exposure to the offending substance, peaks within 15 to 30 minutes and is over within hours.The first symptom is usually a sensation of warmth followed by intense itching - especially on the soles of the feet and palms of the hand. The skin flushes, hives may appear and the face may swell. Breathing becomes difficult, and the person may feel faint and anxious. Convulsions, shock, unconsciousness, even death may follow.
About 60 to 80 percent of anaphylactic deaths are caused by an inability to breathe because swollen airway passages obstruct airflow to the lungs. The second most common cause of anaphylactic deaths - about 24 percent by one estimate - is shock, caused by insufficient blood circulating through the body.
A physician, Dr. Lawrence Lichtenstein, described anaphylaxis as "a dramatic problem which generally has a yes or no outcome: The victim either recovers completely or dies. Fortunately, death is rare."
The frightening and life-threatening symptoms of anaphylaxis are caused by the release of substances known as mediators from mast cells and from basophils, a type of white blood cell. Since the skin and the respiratory and digestive tracts are rich in mast cells, the organs of these systems are the ones primarily affected in the reaction.
Anaphylaxis - like less severe allergic reactions - is an abnormal response to an antigen (a foreign substance, usually a protein) that doesn't bother most people but causes symptoms in those who have an inherited hypersensitivity to it.
Well-known antigens that can cause anaphylaxis include penicillin, insect venom, pollen extracts, fish, shellfish and nuts.
Since the mid-1900s, penicillin has been by far the most common cause of anaphylaxis. Most allergic reactions to penicillin are local skin reactions (e.g., hives, rashes) or systemic reactions (wheezing, swelling, redness).
Insect stings produce another major cause of anaphylactic death. Hymenoptera (honeybees, bumblebees, wasps, hornets, yellow jackets and fire ants) are the offending insects. Although many millions of people in the United States are allergic to insect venom, and hundreds of thousands of them have allergic reactions to stings each year, the number of deaths reported from these reactions is estimated at 50 to 100 per year.
The best way to prevent anaphylaxis is to avoid the instigator (e.g., bees, certain foods).
Those with known sensitivity to insect stings should:
- Avoid areas where they are likely to encounter stinging insects.
- Always wear shoes when walking in grass.
- Avoid smelling like a flower by using perfumes or other scented products, such as scented soaps, aftershaves or suntan lotions.
- Avoid looking like a flower. Don't wear flowered or brightly colored clothing (dark colors like brown and black may provoke an attack; bees are least attracted to white and light khaki).
If prevention doesn't work, be prepared for an attack. Several emergency treatment kits are available by prescription and should always be carried by people who know they are prone to anaphylaxis. All the kits contain epinephrine, which stops the action of the mediators, preloaded in the injecting device. One type contains a notched syringe to ensure the correct dose is given. Other kits contain a spring-loaded injector that automatically injects a predetermined dose of the drug when it is pressed against the thigh.
Some kits also contain a constriction band and an antihistamine. An antihistamine is not an effective emergency treatment. Anaphylaxis must be treated immediately with epinephrine. The constriction band is for use in case of an insect sting on an arm or leg.
If possible, a cold pack should also be applied. The cold causes the blood vessels to constrict, which slows venom getting into the bloodstream.
Emergency kits are not a substitute for professional medical help. They are intended for victims to use until they can reach medical assistance.