Allergic Reactions to Insect Stings, Bee Stings: Causes, Types, Symptoms And Treatment

Allergic Reactions to Insect Stings, Bee Stings: Causes, Types, Symptoms And Treatment

What is an allergic reaction to an insect sting?

Allergic reactions occurring due to a hypersensitivity  reaction to stinging insect venom may occur after a sting from a :

Allergic Reactions to Insect Stings, Bee Stings Causes, Types, Symptoms And Treatment
  • Bee
  • Wasp
  • Yellow jacket
  • Hornet
  • Fire ant
Most people are not allergic to insect stings and may mistake a normal or local reaction for an allergic reaction. By knowing the difference, the patient can prevent unnecessary worry and visits to the doctor’s office or hospital emergency room.

The severity of an insect sting reaction varies from person to person. There are three types of reactions:

  • A normal reaction may result in pain, swelling, and redness around the sting site.
  • A large local reaction may result in swelling that extends beyond the sting site. For example, a person stung on the ankle may have swelling of the entire leg. While it often looks alarming, generally, it resolves on its own and does not progress to a systematic reaction.
  • The most serious reaction to an insect sting is an allergic one (described below). This condition requires immediate medical attention.ct Stings, Bee Stings 

What causes an allergic reaction following a sting?

Insect venom consists of a complex mixture of proteins and peptides. The smaller peptides such as histamine and serotonin are responsible for the painful skin reactions that occur following a sting.

The larger proteins such as phospholipase are responsible for the local and systemic allergic reactions suffered by susceptible individuals. The immune system recognizes these proteins as foreign invaders and mounts an immune reaction against them.

In general, individuals allergic to wasp venoms are susceptible to the venom of other wasp species but react less frequently to bee venom. Those allergic to bee venom may also react to bumblebee venom.

What Are the Symptoms of an Insect Sting Allergy?

Symptoms of a severe insect sting allergy (called an anaphylactic reaction) may include one or more of the following:

  • Difficulty breathing
  • Hives that appear as a red, itchy rash and spread to areas beyond the sting
  • Swelling of the face, throat, or mouth tissue
  • Wheezing or difficulty swallowing
  • Restlessness and anxiety
  • Rapid pulse
  • Dizziness or a sharp drop in blood pressure
Although severe allergic reactions are not that common, they can lead to shock, cardiac arrest, and unconsciousness in 10 minutes or less. This type of reaction can occur within minutes after a sting and can be fatal. Get emergency treatment as soon as possible.

A mild allergic reaction to an insect sting may cause one or more of the following symptoms at the site of the sting:

Allergic Reactions to Insect Stings, Bee Stings Causes, Types, Symptoms And Treatment

  • Pain
  • Redness
  • Pimple-like spots
  • Mild to moderate swelling
  • Warmth at the sting site
  • Itching

People who have experienced an allergic reaction to an insect sting have a 60% chance of a similar or worse reaction if they are stung again.

Who is at risk for insect sting allergies?

Over 2 million Americans are allergic to stinging insects. The degree of allergy varies widely. Most people are not allergic to insect stings, and most insect stings result in only local itching and swelling. Many, however, will have severe allergic reactions. Severe allergic reactions to insect stings are responsible for at least 50 deaths each year in the U.S.

If you are known to be allergic to insect stings, then the next sting is 60% likely to be similar or worse than the previous sting. Since most stings occur in the summer and fall, you are at greatest risk during these months. Males under the age of 20 are the most common victims of serious insect-sting allergic reactions, but this may reflect a greater exposure to insects of males, rather than a true predisposition.

What types of insect sting reactions occur?

Nonallergic reactions

Most insect-sting reactions are not allergic and result in local pain, itching, swelling, and redness at the site of the sting. Some extension of the swelling is expected. Local treatment is usually all that is needed for this type of reaction. Disinfect the area, keep it clean, and apply ice. Topical corticosteroid creams are sometimes used to decrease inflammation, and antihistamines can help control itching.

Large local reactions may involve increased swelling (that lasts for 48 hours up to one week) that may be accompanied by nausea and vomiting. Large local reactions occur in about 10% of insect stings and are not allergic in origin. Occasionally, the site of an insect sting will become infected, and antibiotics are needed.

Allergic reactions

Systemic (body-wide) reactions are allergic responses and occur in people who have developed antibodies against the insect venom from a prior exposure. It is estimated that between 0.3%-3% of stings trigger a systemic allergic reaction.

The allergic reaction to an insect sting varies from person to person. Symptoms of an allergic reaction can include itching, hives, flushing of the skin, tingling or itching inside the mouth, and nausea or vomiting. The most serious allergic reaction is called anaphylaxis, which can be fatal. Difficulty breathing, swallowing, hoarseness, swelling of the tongue, dizziness, and fainting are signs of a severe allergic reaction. These types of reactions usually occur within minutes of the sting but have been known to be delayed for up to 24 hours. Prompt treatment is essential, and emergency help is often needed.

How are normal or localized reactions treated?

First, if stung on the hand, remove any rings on your fingers immediately. A stinging insect may leave a sac of venom and a stinger in the victim's skin. If the sac is still in the skin, gently scrape it out with a fingernail or a stiff-edged object like a credit card. Do not pull on the stinger as this will cause the release of more venom into the skin.

Wash the stung area with soap and water then apply an antiseptic.

Apply a soothing ointment, like a hydrocortisone cream or calamine lotion and cover the area with a dry, sterile bandage.

If swelling is a problem, apply an ice pack or cold compress to the area.

Take an oral anti-histamine, like Benadryl, to reduce itching, swelling and hives. However, this medication should not be given to children under 3 years of age or to a pregnant woman without prior approval from a doctor.

To relieve pain, take aspirin or an aspirin-substitute. However, do not give a child or teenager aspirin. (Aspirin use in these age groups has been associated with a rare but serious liver and brain disorder called Reye's syndrome).

In general, pregnant women should consult their doctor before taking any over-the-counter medication.
Also, it is always recommended that you read the warning label on any medication prior to taking it. Parents of children and people with medical conditions are advised to read product labels carefully and consult a pharmacist if they have questions about use.

How Are Allergic Sting Reactions Treated?

Severe allergic sting reactions are treated with epinephrine (adrenaline), either self-injected or administered by a doctor. Usually this injection will stop the development of a more severe allergic reaction.

In some cases, intravenous fluids, oxygen, and other treatments are also necessary. Once stabilized, you are sometimes required to stay overnight at the hospital under close observation. People who have had previous allergic reactions to an insect sting must remember to carry epinephrine with them wherever they go. Also, because one dose may not be enough to reverse an allergic reaction, immediate medical attention following an insect sting is still recommended.

How Can I Avoid Being Stung?

You can lessen your chances of an insect sting by taking certain precautionary measures:

Learn to recognize insect nests and avoid them. Yellow jackets nest in the ground in dirt mounds or old logs and walls. Honeybees nest in beehives. Hornets and wasps nest in bushes, trees, and on buildings.

Wear shoes and socks when outdoors.

Wear long-sleeved shirts, long pants, socks, and shoes when in rural or wooded areas.

Avoid wearing perfumes or brightly colored clothing. They tend to attract insects.

If you have severe allergies, you should never be alone when hiking, boating, swimming, golfing, or otherwise involved outdoors because you might need prompt medical treatment if stung.

Use insect screens on windows and doors at home. Use insect repellents. Spray bedrooms with aerosols containing insecticide before going to bed.

Spray garbage cans regularly with insecticide and keep the cans covered.

Avoid or remove insect-attracting plants and vines growing in and around the house.

A severely allergic person should always wear a MedicAlert bracelet and keep a self-care kit (described below) on hand for emergency use in the case of severe symptoms.

How can I prevent an allergic reaction?

Allergic reactions to insect stings can be prevented with venom immunotherapy. The treatment is at least 97% effective in preventing future occurrences. It involves administering gradually increasing doses of venom to stimulate the patient's own immune system to become resistant to a future allergic reaction.

What can I do about becoming immune to insect allergy?

All people who have had a significant reaction to a stinging insect should be evaluated by an allergy specialist for possible venom immunotherapy (allergy shots that develop an immunity to insect allergy). Selected patients with significant sensitivity to insect venom and specific symptoms can undergo allergy injection therapy for stinging-insect allergy. Allergy immunotherapy against stinging insects in these selected patients is almost 100% effective.

This type of treatment usually involves a gradually increasing dose of the venom over 10-20 weeks. Then a "maintenance" dosage every four to eight weeks is given. After approximately three to five years, discontinuation of the venom shot is considered. Therapy for three to five years confers long-term protection in most people. The risk of severe adverse reactions from this venom therapy is minimal (less than 0.2%), and no deaths have been reported to date.

The U.S. Department of Agriculture recommends the following:

  • Avoid disturbing likely beehive sites, such as large trees, tree stumps, logs, and large rocks.
  • If a colony is disturbed, run and find cover as soon as possible. Running in a zigzag pattern may be helpful.
  • Never stand still or crawl into a hole or other space with no way out.
  • Do not slap at the bees.
  • Cover as much of the head and face as possible, without obscuring vision, while running.
  • Once clear of the bees, remove stingers and seek medical care if necessary, especially if there is a history of allergy to bee venom.

How can I find out more about venom immunotherapy?

If you've had an allergic reaction, it's important to seek information from an allergist, a doctor who specializes in the diagnosis and treatment of allergic disease. Based on your history and diagnostic tests, the allergist will determine if you are a candidate for immunotherapy treatment. Although stinging insect allergy is a serious problem, the risk and fear of allergic reactions can be reduced or eliminated with immunotherapy.

What are Epinephrine sting kits?

Epinephrine self-administration kits are important for a patient to use before he or she can get to a physician for treatment. However, epinephrine kits should not be used as a substitute for an allergy evaluation and physician intervention. Epinephrine alone is not always enough to reverse serious allergic sting reactions and may cause serious side effects in some patients with heart conditions or patients who are taking certain medications. Before using, be sure to check with your physician to prevent drug interactions.