Insect Bite and Sting Allergy

Allergic Reactions to an Insect Bite or Sting

Learn about insect bites and stings. © US Dept of Agriculture

Nearly everyone has experienced an insect bite or sting at some point in their lives. Most of the time, these stings and bites lead to mild pain or itching right where they occurred. Sometimes, however, people can experience more severe reactions that could be caused by an allergic reaction to the sting or bite. Allergic reactions most commonly occur with bites or stings from these insects.

Bees, Wasps, Yellow Jackets and Hornets

Most people who are stung by these insects will develop a reaction at the site of the sting that will cause pain, swelling, redness and itching.

A smaller percent of people -- about 10 to 15% -- also will experience larger areas of swelling, and the swelling can last up to a week. Rarer still are people who have full-blown allergic reactions that cause anaphylaxis. About 0.5% of children and 3% of adults will experience anaphylaxis after a sting from these insects.

Learn more about reactions to bee stings.


Most people experience some form of reaction from mosquito bites -- the typical itchy red bumps that last for a couple of days. Less commonly, more severe reactions can occur. These include blistering rashes, bruises, or large areas of swelling at the bite sites. People who experience extremely large areas of swelling after a mosquito bite (such as swelling of most of an arm or leg, for example) have been dubbed as having "skeeter syndrome." Rarely, anaphylaxis can occur as a result of a mosquito bite.

Learn more about reactions to mosquito bites.

Fire Ants

Fire ants are aggressive stinging ants found most commonly in the southern United States. Almost everyone experiences some sort of reaction to a fire ant sting, the most common of which is a sterile pustule at the site of the sting. A large percentage of people experience a large amount of swelling, redness and itching around the site of the sting (these are called large local reactions).

About 1% of people can experience severe allergic reactions, such as anaphylaxis, as a result of a fire ant sting.

Learn more about reactions to fire ants.


Bedbugs are flat wingless insects, typically of a brown or reddish color, about half the size of a dime. These insects are blood-sucking parasites, and they usually feed at night -- mostly on people. Bedbug bites can appear as itchy, red bumps and are frequently confused with allergic rashes. The rash may be grouped in a line, which shows the pattern of the insect feeding.

Learn more about reactions to bedbug bites.


Scorpions are found around the world. They are not insects; they are arachnids and are closely related to spiders, mites and ticks. Scorpions have the ability to kill prey by injecting venom from a stinger located at the end of a long tail. Because many scorpions are found indoors, people are frequently stung by scorpions. Scorpion stings are rarely known to sometimes cause allergic reactions, although in most cases, symptoms after a scorpion sting are caused by neurotoxins in the venom, leading to symptoms of numbness and tingling throughout the body.

Learn more about reactions to scorpion stings.


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