When the warm weather arrives, many people enjoy spending time in the great outdoors. But with the outdoors comes insects. Most insects are harmless. They are actually good for the environment. Some, like mosquitoes, inflict painful or irritating insect bites and can spread disease. Other insects sting and release venom.
For most people, getting stung by an insect is a short-term annoyance. For others, an allergy to the venom from a stinging insect can cause an allergic reaction. Sometimes these reactions are severe and cause anaphylaxis. This requires medical treatment.
Which insects cause allergic reactions?
Many people have a stinging insect allergy but it’s rare to experience anaphylaxis after a sting. Any kind of insect venom, such as from a bee sting or wasp sting, can cause an allergic reaction.
The following are the most common insects that can cause a serious allergic reaction. A serious reaction can be life threatening and require immediate medical attention.
Yellow jackets
Also called ground bees, yellow jackets are part of the wasp family. Some yellow jackets build their nests underground or in fallen logs. Others nest in the walls of houses. These black and yellow insects swarm around picnic areas and trash cans. They are persistent in their search for food and aggressive if you get in their way.
From spring to midsummer, they forage for protein (insects or other meat) to feed the larvae in the nest. They also look for sweets for themselves and the other adults. By late summer, their numbers peak and they go on a frenzied search for sweets wherever they can find them. They especially love summer picnic foods and drinks! A yellow jacket sting is an unpleasant way to end a lovely summer day. They will often sting numerous times, especially if provoked.
Hornets
Hornets are slightly larger than yellow jackets. They are more the size of a bumble bee but with a defined, narrow waist – and most are black with white or yellow stripes. Hornets are often feared because of their size. But hornets do not usually sting people unless provoked.
Hornets are natural predators. They kill other insects and even caterpillars to feed the larvae in their nest. Adults eat nectar and fruit pulp.
In the spring, the queen will build a small nest the size of a golf ball high in a tree or under the eaves of a building. Workers add layers throughout the summer as more insects hatch. Their nests can become as large as a football, always with the opening facing down.
Paper wasps
Longer and slimmer than bees or hornets, paper wasps drag their long legs behind them as they fly. Their coloring ranges from reddish brown to black, with yellowish rings. Wasps eat other insects and spiders but will also forage for food in picnic areas and garbage cans.
They have a habit of building (and defending) their nests on and around homes and small buildings. This makes them common garden pests. You can recognize a wasp’s nest by its papier-mâché look. They also have an interconnected web of cells, which are homes for the young wasps.
Some nests are small, with only a dozen or so wasps; others house up to 100 insects. They often hang from trees or under eaves. They sometimes look like upside-down umbrellas. Some paper wasps build nests inside cavities such as bird boxes.
Bees
When many people think if stings, they think of bee stings. There are several kinds of bees that sting and can cause severe reactions.
Honeybees are fat, dark brown, slightly hairy insects. They are often found hovering around bright flowers or feasting on clover. Found most often in warm climates, these are the bees of folklore that build hives and produce honey. Honeybees will use the same nest year after year. They build elaborate honeycombs and live on the stored honey over the winter. They can only sting once, leaving their stinger behind in the skin, then dying.
Their cousins, the bumble bees, look very similar but will sting more than once if threatened. Bees build their hives in protected areas. You might find them in building cavities, holes in the ground, or compost piles. Bumble bees start new nests each spring.
Africanized honeybees are sometimes called killer bees. They are a subspecies of honeybees with a reputation of being extremely aggressive. Like the honeybee, they can sting only once, but their hives are so large that they attack in swarms if you get too close. Always get professional help to remove a beehive.
Bee sting allergy treatment depends on how severe the symptoms are. For a mild reaction, such as localized pain, itching, or swelling, you can treat at home. This is a normal reaction and not truly an allergic reaction.
For a serious anaphylactic reaction, the treatment is epinephrine. Use epinephrine first and fast and then seek emergency treatment.
Fire ants (or red ants)
Fire ants have been in the United States for more than 100 years.They are typically found in southern regions of the United States and as far west as California. Fire ants often nest in sunny, sandy areas, at the edges of riverbanks and ponds, and in moist areas such as irrigated lawns. With the warming climate, fire ants are migrating further north. They typically do not survive in cold climates.
Fire ants are black and red or reddish-brown in color and 1/8 to 1/4 inch in length.
The best way to know you’re around fire ants is to recognize their nests. They are large, dome-shaped mounds of crumbly earth. They can be up to 18 inches across and 8-12 inches high. The ants come and go through underground tunnels. The mounds do not have visible openings like traditional ant mounds. If you step on the nest, the ants will quickly swarm up onto your feet and legs.
If you live in fire ant country, be careful walking in grassy areas. Fire ant stings can cause a burning sensation and raised welts. As the ants are normally in mounds on the ground, it is most common to get stung on the feet and legs.
In most people, a fire ant sting results in an itchy red rash or lump at the sting site. A few hours later, a small blister appears that fills up with pus-like liquid. Topical ointments and oral antihistamines may relieve the itching.
People with a fire ant sting allergy are at risk for anaphylaxis. The treatment is epinephrine. Some fire ants are very aggressive. They can sting again and again, increasing the risk for a severe allergic reaction.
What are common insect sting allergy symptoms?
Symptoms of insect venom allergy can range from mild to severe. Mild reactions are normal and not considered an allergy. A systemic severe reaction can be anaphylaxis. The danger is that an allergic reaction can happen to anyone, even if you have no other allergies. Even people who have been stung before without problems can become allergic.
Local reaction
The most common reaction is swelling, pain and itching centered around the site of the sting. This is your body’s response to the irritating enzymes and chemicals in the insect’s venom. This is normal and it is not an allergic reaction. A cold compress or ice is the best treatment. You may also try antihistamines or calamine lotion to control itching.
Systemic (whole body) reaction
A systemic reaction will set off symptoms in other parts of the body, away from the sting. These severe allergic reactions are a whole body reaction. The most common symptoms are skin-related, such as hives (a raised, itchy rash) or deep swelling.
Anaphylaxis
A life-threatening allergic reaction is called anaphylaxis. It is the most serious reaction to an insect sting and it’s a medical emergency. Anaphylaxis spreads quickly through multiple systems in the body. Early symptoms include hives and swelling in the mouth and throat. You may develop dizziness, headache, trouble breathing, nausea, or vomiting. It can result in a sudden drop in blood pressure and loss of consciousness. These symptoms require immediate medical attention.
The only treatment for a life-threatening allergic reactions is epinephrine. If you have epinephrine with you at the time of the insect sting, use it right away if you think you are experiencing a severe allergic reaction.
Insect sting symptoms usually occur quickly, sometimes within 10 minutes. The sooner you receive treatment, the more likely the symptoms are to improve. It is impossible to predict whether symptoms will progress from mild to life-threatening. So it’s safer to immediately administer epinephrine than to wait to see what happens. Delaying epinephrine increases the risk of complications.
Follow up with medical care if symptoms linger. Insect sting anaphylaxis can come back after the epinephrine wears off (after 30 minutes).
What do you do for an insect sting?
The best thing you can do is to avoid the insect in the first place. You can do this by:
- Avoiding areas that attract insects.
- Keeping drinks and food covered.
- Flicking the insect away from your skin.
- Remaining calm if you see an insect. Walk (don’t run) away from the area. Some insects find quick movements threatening. Running can also increase your body’s absorption of venom.
If you do get stung, here’s what you can do:
- If a stinger is left in the skin (the telltale mark of a honeybee), scrape it off with a flat surface. You can use something like a credit card to do this. Do not use tweezers or your fingertips, as that could squeeze more venom into the sting area.
- Wash the area with soap and water.
- Apply a cold compress or ice to reduce swelling.
- Expect local redness and swelling.
- You can also apply a paste of baking soda and water or an over-the-counter product for insect stings.
Signs and Symptoms of Anaphylaxis
- Hives or generalized itching at the stinging site and/or other parts of the body
- Swelling of the throat or tongue
- Difficulty breathing or wheezing
- A raspy voice
- Dizziness
- Severe headache
- Stomach pain or cramps, nausea or diarrhea
How is an insect allergy treated?
Anaphylaxis requires immediate treatment with epinephrine. This should be followed up with care in an emergency room if symptoms persist.
People at risk of a severe aller should always carry epinephrine. They also need to know how to properly use their epinephrine device. For an insect sting, it’s important to have two doses of epinephrine available in case symptoms recur after the first dose. Check expiration dates and replace when necessary. Epinephrine should be stored at room temperature, away from extreme heat or cold.
Insect venom immunotherapy, or allergy shots, are also an option. These are for prevention of future allergic reactions to an insect sting allergy.
What is insect venom immunotherapy?
Insect venom immunotherapy involves a gradual build-up in tolerance to the insect venom. It is administered as a series of allergy shots. Insect venom immunotherapy is very effective at long-term prevention of allergic reactions from an insect sting. It provides many people with years of protection from stinging insect allergy.
Here is how it works: your allergist will conduct tests to determine the severity of your venom allergy. This will confirm for the allergist whether immunotherapy is appropriate. Then, the treatment is done in two stages.
- Patients are given a series of shots with gradually increasing amounts of the insect venom allergen. The series of shots is administered once a week for 8-20 weeks. It’s designed to help your body build immunity. At the end of this phase, you reach the maximum dose. At this point, your body should be fully protected from insect venom.
- Patients are given booster shots every 1-2 months for long-lasting immunity.
After five years of treatment, most people can stop immunotherapy and never have another allergic reaction to a sting.
Questions & Answers (Q & A) on insect sting allergy
Here are some of the most commonly asked questions on insect sting allergy or insect bite allergy treatment.
Patient Story: Beekeeping With a Honeybee Allergy
Jennifer Ford is a science teacher and co-owner of Bees of the Woods Apiary in Altamont, New York.
When I first started beekeeping, I experienced normal reactions to bee stings. These were often a burning sensation, redness, itching and swelling at the site of the sting. Since then, I’ve developed a honeybee venom allergy. Fortunately, I’m able to continue my work as a beekeeper.
I first experienced honeybee allergy symptoms a few years after my husband Keith and I opened our beekeeping business. We were removing a colony of honeybees from the wall of an old shed. It was a long, hot process. By the end, both the humans and the honeybees were feeling pretty grouchy. As I was finishing up, I was stung three times.
I’d never had a serious problem with bee stings before, so I didn’t think too much of it.
On the way home, I noticed my lips, tongue and throat felt slightly swollen, but my breathing was fine. A few days later, we went back to collect the remaining bees and I was stung again. I experienced the same swelling. I realized it was an allergic response to the honeybee venom. I was lucky symptoms were not more severe.
Going to an Allergist
I decided to see an allergist. The allergist scheduled me for skin tests using different types of stinging insect venom. The results showed I had developed an allergy to honeybee venom. Luckily my reactions were not severe.
I was prepared to hear that I would have to give up beekeeping. With every subsequent sting, there was a good chance my allergic reactions would worsen. However, my allergist told me there were other options. If I wanted to keep working with bees, there were three things I needed to do.
- Use more protective gear to avoid stings. For me, this meant wearing coverall pants and a jacket. I also had to wear gloves. (In the past I had preferred to work with bare hands.)
- Always carry an epinephrine auto-injector.
- Schedule appointments with my allergist for immunotherapy shots. This would help desensitize me to honeybee venom.
Venom Immunotherapy
I started getting immunotherapy shots once a week. This was initially a large time commitment, but it gradually tapered off.
The treatment worked! I was stung a few times after starting immunotherapy, with no reaction at all. The immunotherapy shot was not very painful – no worse than a bee sting. I never had an adverse reaction to the shots.
I worked my way up to one shot every six weeks, but then I had a setback. I was stung while moving a honeybee colony and experienced another allergic reaction. My allergist dropped me back to one shot every four weeks. I will probably need to continue immunotherapy shots as long as I continue to keep bees.
Immunotherapy is worth it to me because I love beekeeping. I don’t feel as anxious while I am in the bee yard anymore, either.
If you have ever experienced an allergic reaction to an insect sting, I highly recommend seeing an allergist. Get tested and find out if immunotherapy is right for you!
Reviewed by:
Purvi Parikh, MD, FACAAI is an adult and pediatric allergist and immunologist at Allergy and Asthma Associates of Murray Hill in New York City. She is on faculty as Clinical Assistant Professor in both departments of Medicine and Pediatrics at New York University School of Medicine.