Bee and Wasp Stings

Wasp venom may cause allergic reactions.

Although many different types of insects in the United States are able to inflict a poisonous bite or sting (meaning they are venomous), the insects most likely to cause medical problems are bees (including the domestic honey bee, its Africanized "killer bee" race, and the bumble bee), wasps (including paper wasps, hornets, and yellow jackets), and ants (including the fire ant).

These insects are all in the Hymenoptera order, and thus stings from them are occasionally called Hymenoptera stings.

Because many of these species live in colonies, if one stings you, you may be stung by many.

Although most stings cause only minor medical problems, some stings may cause serious medical problems and even death.

Bees and wasps inject venom by stinging unlucky people. Sometimes-especially with bees-the stinger may be left in the skin. The venom is poisonous and may cause direct injury to the human body. This injury is usually confined to the areas close to the sting or stings.

• Allergic reaction: The vast majority of serious medical problems and deaths result from an allergic reaction. This happens in certain people whose immune systems are overly sensitive (or allergic) to the venom. When they get stung, their body may overreact to the venom, and an allergic reaction may happen throughout their body. These people are frequently described as being allergic to specific insect stings.
  • Some people may die from insect venom anaphylaxis (severe allergic reaction). These fatal allergic reactions frequently, but not always, occur in people who have had a previous allergic reaction to the same type of insect.
  • Although multiple stings increase the potential danger in allergic cases, a serious or even fatal allergic reaction can (and does) occur from a single sting in a person with no known prior allergic reaction.
  • The vast majority of serious and fatal allergic reactions from stings cause a significant and obvious allergic reaction within an hour of being stung. Most deaths from stings occur within the first hour. Immediate emergency medical care is critical in known or suspected allergic reactions after an insect sting. In rare cases, serious or even fatal allergic reactions may not happen for up to four or more hours after an insect sting.

• Other complications: Insect stings in nonallergic people, though perhaps painful, usually do not cause serious problems. However, multiple stings may cause serious complications (such as muscle breakdown or kidney failure) and, rarely, even death in nonallergic people.
  • Especially at increased risk are small children, elderly people, and people who are already weak. These serious problems may occur within the first few hours of being stung or may be delayed for days after being stung.
  • Even a single sting in the mouth or throat can cause swelling and obstruction of the airway. Children are at increased risk for these types of breathing problems from a sting.
  • A bacterial skin infection at the sting site may also develop.

The severity of a sting is determined by a number of factors. The type of insect, the location of the sting, the number of stings, and the allergic sensitivity of the victim can all affect the outcome. Most people do not have allergic reactions to bee and wasp stings.

Medical problems from bee and wasp stings are broadly broken down into two categories:

• Local reactions (only the part of the body near the sting is affected)
  • Immediate pain, redness, swelling, and itching at the sting site may occur.
  • A large (greater than four inches across) local reaction may develop over the next 12-36 hours.
  • A bacterial skin infection, although uncommon, may also begin during the first 12-36 hours (or even after the first few days).
  • These may cause an enlarging area of redness at the sting site. It may be difficult to tell a local skin reaction and a local bacterial skin infection apart.
  • Systemic or allergic reactions (parts of the body away from the sting are affected)
    • Hives (raised itchy bumps on the skin) and itching all over the body
    • Swelling of the mouth or throat or both
    • Wheezing
    • Shortness of breath or other difficulty breathing
    • Nausea
    • Vomiting
    • Anxiety
    • Chest pain
    • Low blood pressure (weakness or fainting)
  • In severe cases, marked difficulty breathing, unconsciousness, and even death may occur.

Although most stings can be treated at home, some will require more medical care.

• Call your doctor or go to a hospital's emergency department if a large localized reaction (greater than about 10 inches in diameter) occurs, evidence of infection (increasing pain, swelling, redness, drainage of pus or fever) is present at the sting site, or any symptoms last for more than a day or two.
• If it has been more than 10 years since your last tetanus booster immunization, contact your doctor about getting a tetanus immunization.

Although most stings do not require medical care, remember some stings can be serious or even fatal. If you have the slightest suspicion that someone is having a generalized or allergic reaction, seek emergency medical care immediately. In many areas dialing 911 for an ambulance may be your best option. (Try to avoid driving yourself to the hospital if you believe you are suffering from an allergic reaction-you may lose consciousness and have an accident.)

Go to a hospital's emergency department immediately if someone is showing evidence of an allergic reaction. Remember, an allergic reaction may occur in people with no prior history of allergic reactions. Any of the following may indicate an allergic reaction:

• Difficulty breathing
• Difficulty speaking
• Swelling in the mouth or throat
• Rash all over the body
• Faintness or decreased level of consciousness
• If more than 10-20 stings have occurred, especially with wasp stings or in children, elderly people, or people with underlying medical problems
• If the sting involves the inside of the mouth or throat, especially if in children and/or involves more than one sting
• If the sting involves the eyeball itself
• If a person has been stung by an insect species that has previously caused an allergic reaction in the person-even if there is no evidence of a current allergic reaction (The safe thing to do is to head for an emergency department in case the person suddenly develops an allergic reaction.)
• If a large localized reaction (redness greater than about 10 inches across) or evidence of infection (increasing pain, swelling, redness, drainage of pus or fever) is present at the sting site or sites and you cannot contact your personal doctor promptly

Emergency department evaluation will likely first include checking the vital signs (blood pressure, pulse, breathing rate, and temperature). The doctor will then focus on examining you for evidence of breathing or airway difficulties, shock, and widespread rash.

A history, including current medications, underlying medical problems, and previous allergic reactions, will be obtained.

Your physical examination and vital signs will largely determine what treatment is given. Blood work, x-rays, and other tests are rarely needed.

Treatment will depend on the severity of your condition. It is important to note that no specific antivenom is available to counteract the poison injected by the insect. The majority of problems requiring medical treatment result from the allergic reaction to the sting. Many of the complications from an allergic reaction respond well to various medications-when given in time.

• Most simple insect stings in a nonallergic person require no more than first aid at home.
• Avoid further stings by wearing protective clothing, using insect repellant, and avoiding infested areas.
• Remove any stingers remaining in the skin (most likely from bees) immediately. Some experts recommend scraping out the stinger with a credit card. However, it is probably more important to get the stinger out as quickly as possible than to be overly concerned about how it is removed.
• Application of ice to the sting site may provide some mild relief. Ice may be applied for 20 minutes once every hour as needed. Cloth should be placed between the ice and skin to avoid freezing the skin.
• Consider taking an antihistamine such as diphenhydramine (Benadryl) for itching.
• Consider taking ibuprofen (Motrin) or acetaminophen (Tylenol) for pain relief as needed.
• Wash the sting site with soap and water. Place an antibiotic ointment on the sting site.
• If it has been more than 10 years since your last tetanus booster immunization, get a booster within the next few days.
• Most insect stings require no additional medical care. More serious reactions may need immediate medical care.
• If you have been stung by a bee or wasp and have previously had a serious allergic reaction, seek medical attention. Consider taking an antihistamine such as diphenhydramine (Benadryl) as soon as possible. If any allergic symptoms develop, consider using the epinephrine part of an emergency allergy kit (EpiPen) if previously prescribed by a doctor.

• If you have a single sting with no allergic symptoms, you may require only local wound care (such as cleaning and antibiotic ointment). Any retained stingers will be removed. Itching may be treated with an oral antihistamine such as diphenhydramine (Benadryl). Pain may be treated with medicine such as ibuprofen (Motrin), acetaminophen (Tylenol), or both. Also tetanus immunization will be given as indicated.
• If you have mild allergic symptoms (such as a rash and itching all over the body but no problems breathing or with your vital signs), you may be treated with an antihistamine. You may also be given steroids. In some cases, you may also be given an epinephrine (adrenaline) injection. Some of these treatments may be given at the scene or in the ambulance by emergency medics. You may be sent home if you are doing well after observation in the emergency department.
• If you have a more moderate allergic reaction (such as rash all over the body, and some mild problems breathing), you will likely receive injections of antihistamines, steroids, and epinephrine. Some of these treatments may be given at the scene or in the ambulance by emergency medics. You will likely need to be observed for a prolonged period of time in the emergency department. You may need to be admitted in the hospital.
• If you have a severe allergic reaction (such as low blood pressure, swelling blocking air getting into the lungs, and/or other serious problems breathing), you have a true life-threatening emergency. Treatment may include placement of a breathing tube into your trachea. You will likely be given injections of antihistamines, steroids, and epinephrine. IV fluids may also be given. Some of these treatments may be given at the scene or in the ambulance by emergency medics. You will be closely monitored in the emergency department and likely admitted into the hospital-perhaps the intensive care unit.
• If you have multiple stings (more than at least 10-20 stings) but no evidence of an allergic type reaction, you sometimes may require prolonged observation in the emergency department or admission into the hospital. Multiple blood tests may be indicated.
• If you are stung inside the mouth or throat, you may simply require observation in the emergency department, or you may need more intensive management if complications develop.
• If you are stung on the eyeball, you may require consultation or evaluation by an ophthalmologist (an eye doctor).

Take any medication prescribed for you as directed. This may include an antihistamine such as diphenhydramine (Benadryl) and a steroid such as prednisone.

• If you have been prescribed a self-administered injectable epinephrine emergency sting kit, such as an EpiPen, get as many kits as needed as soon as possible. Replace them after use.
• If you develop (or redevelop) difficulty breathing or swelling in the mouth or throat after leaving the doctor, go to the hospital immediately.
• If you develop decreased urination or dark-colored urine (especially if you suffered multiple stings), seek prompt medical attention from your doctor or emergency department.
• If the sting site looks infected (worsening swelling, redness, drainage of pus), or if you develop a fever, seek prompt medical attention from your doctor or emergency department.
• If you have suffered a significant allergic reaction from a sting, be sure to discuss with your doctor possible future use of a self-administered injectable epinephrine emergency sting kit, such as an EpiPen, and referral to an allergist.

Some, but not all, stings can be prevented. It is especially important that people known to be allergic to certain insects make an effort to avoid those insects.

Ways to avoid stings include the following:

• Avoid known areas of concentration such as hives and nests.
• Do not molest hives and nests.
• Take care with motorized equipment such as lawnmowers, because they may provoke the insects.
• If flying insects are around, leave the area and refrain from swatting at them.
• Avoid activities outdoors with sugary drinks, brightly colored clothing, and strong fragrances or perfumes because some insects may be attracted to them.
• Wear long pants and long-sleeved shirts because they may also provide some protection.
• Keep outdoor dining and camping areas clean and free from garbage.

If you have had a previous significant allergic reaction to a sting, it is very important that you have readily available (and know when and how to use) a self-administered injectable epinephrine emergency sting kit, such as an EpiPen.

• Proper use of these kits may literally be life-saving until emergency help can be reached.
• It is important that a proper kit be readily available. Multiple kits may be needed to have one at home, at work, in a purse, and in your car.
• If you are allergic to bee or wasp stings, talk about these kits with your doctor.

If you have had a prior significant allergic reaction to a sting, talk to your doctor about seeing an allergy specialist. Immunotherapy, a series of shots of low-dose sting venom, may reduce the risk of future severe allergic reactions from similar stings from about 60% to about 5%.

If you have had a prior significant allergic reaction to a sting, consider wearing a Medic Alert bracelet and carrying an emergency medical allergy card in your wallet or purse.

• In most cases involving only one or a few stings, the prognosis is excellent if only local symptoms occur. Pain and itching may last a day or so.
• Cases involving many stings may occasionally cause delayed and long-term complications. Although these complications may occur despite appropriate medical care, early medical care may lessen the severity.
• Serious skin infections are uncommon after a sting.
• People suffering a mild allergic reaction are likely to do well if emergency medical care is sought quickly.
• People who suffer a severe allergic reaction to a sting require immediate emergency medical care to lessen the chance of serious illness or even death. Any delay in emergency medical care greatly increases the risk to a person having a severe allergic reaction. In some allergic people, severe disability or even death may still occur despite appropriate medical care.