Having your pleasant spring or summer day interrupted by a bee sting can be more than just an inconvenience. Bee stings can cause significant allergic and, in some cases, life threatening reactions and can be frightening. Indeed, five species of bees cause most stings with approximately 0.5% of the population being at risk for a significant allergic reaction and up to 50 fatalities being reported each year.

Allergic reactions to bee stings are generally classified according to the time interval between the sting and reaction, and the extent of the reaction. Immediate reactions occur up to four hours after the sting; delayed reactions occur later.

Of the immediate reactions, most are localized at the sting site, very itchy with swelling, pain and redness. Reactions can be quite large, but other than discomfort, the reaction poses no health risk. Immediate reactions can also be systemic, involving signs and symptoms remote from the sting site. Systemic reactions usually involve generalized itching, redness, swelling and hives.

Studies have shown that under the age of 16, an individual who develops either localized or mild systemic reactions from bee stings has no increased risk for worse reactions with subsequent stings. In contrast, adults who have experienced systemic reactions and who have positive venom skin tests are at 40-60% risk for another significant or worse systemic reaction.

A small percent of children and adults may develop serious, life-threatening reactions called anaphylaxis, consisting of hives, swelling, shortness of breath, wheezing, low blood pressure (hypotension), abdominal cramping and altered consciousness. Toxic reactions resemble systemic reactions, but occur when multiple (50-100) stings are received in a short period.

Localized and mild systemic reactions can be treated at home with antihistamines. Significant systemic reactions often require emergency room treatment with adrenaline (epinephrine), intravenous fluids and steroids. Patients at any age who have experienced life threatening systemic reactions and individuals age 16 and older who have experienced systemic reactions should have intradermal skin testing to diagnose bee sting allergy. If tests are positive, bee venom allergy shots (immunotherapy) are recommended, and individuals should carry Benadryl and epinephrine. Epinephrine is available in a pre-loaded syringe and in a spring-loaded syringe called an autoinjector. Both should be kept on hand at all times. The latest 1996 study out of Johns Hopkins University claims that five years of venom immunotherapy may be adequate for most patients.