Bedbug Allergies

Allergy to Bedbug Bites

Bed bug
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What are Bedbugs?

Bedbugs, scientific name Cimex lectularius, are a flat wingless insect, typically of a brown or reddish color. It is typically about half of a centimeter in length (about half the size of a dime). These insects are blood-sucking parasites, and usually feed at night – mostly on people. Feedings typically last about 5 to 10 minutes, and these insects can go months between meals, making them difficult to eradicate.

Bedbugs can be difficult to find, as they tend to hide during the day, although can leave clues to their presence. These include black specks on sheets and mattresses, which are a mix of droppings and other body parts. These insects tend to be found in hotels, homeless shelters, and overcrowd areas, although can also be found in areas of high socioeconomic status.

Do Bedbugs Cause Rashes?

Bedbug bites can be mistaken for allergic rashes, especially urticaria. Bites appear as itchy bumps on skin that is uncovered while sleeping. The rash may be grouped in a line, which shows the pattern of the insect feeding. Bumps tend to be redder in the morning and fade later in the day.

Can I Be Allergic to Bedbugs?

Most people bitten by bedbugs assume that they have experienced an allergic reaction to something. The reaction is typically an irritant effect to the insect bite, and not an allergy. While most people are not allergic to bedbugs, there are rare reports of anaphylaxis occurring as a result of bedbug bites.

What Can Be Done for Bedbug Bites?

Physicians may misdiagnose bedbug bites as allergic reactions, and treat people with steroid pills, creams or antihistamines. While antihistamines may decrease the itching associated with the insect bites, these medications will not make the rash go away. Steroid creams, such as hydrocortisone (Cortaid, for example), can help the itch and rash resolve quickly.

Do Bedbugs Cause Other Problems?

If the bumps from bedbugs are scratched to the point of breaking the skin, the bite may become infected. This may appear as increased pain, redness or oozing at the site, and may worsen, rather than get better, over time. If this occurs, immediate medical attention is needed.

It appears possible that bedbugs may be able to transmit the hepatitis B virus, as this virus has been found in bedbug droppings.

Bedbugs may also be able to transmit the parasite Trypanosoma cruzi, which causes Chagas Disease.

What Can I Do About Bedbugs?

The best way to deal with bedbugs is by extermination. Professional pest control companies can assist with the extermination process, usually with pesticide treatments. Sleeping in long-sleeved shirts and pants may decrease the amount of skin available to be bitten, and some studies suggest that using insect repellents containing DEET may prevent the insects from biting.

Want to keep learning? Find out more about insect allergies.


Scarupa MD, Economides A. Bedbug Bits Masquerading As Urticaria. J Allergy Clin Immunol. 2006; 117:1508-9.

Bedbug Bites Often Misdiagnosed as Allergic Skin Rashes. Review of Allergy, Asthma and Immunology. March-April 2007:19.

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