Health Conditions A-Z Skin, Hair & Nail Conditions Bed Bug Bites vs. Flea Bites: How To Tell the Difference There are a few telltale signs that can help you discern what kind of bite you have. By Maggie O'Neill Maggie O'Neill Maggie O’Neill is a health writer and reporter based in New York who specializes in covering medical research and emerging wellness trends, with a focus on cancer and addiction. Prior to her time at Health, her work appeared in the Observer, Good Housekeeping, CNN, and Vice. She was a fellow of the Association of Health Care Journalists’ 2020 class on Women’s Health Journalism and 2021 class on Cancer Reporting. In her spare time, she likes meditating, watching TikToks, and playing fetch with her dog, Finnegan. health's editorial guidelines Updated on December 12, 2022 Medically reviewed by Corinne Savides Happel, MD Medically reviewed by Corinne Savides Happel, MD Corinne Savides Happel, MD, is an allergist and assistant professor at the John Hopkins School of Medicine. learn more Share this page on Facebook Share this page on Twitter Share this page on Pinterest Email this page Bug bites are annoying for multiple reasons, one of which is that it's not always easy to know what kind of insect is to blame for the bites. Many bug bites look and feel similar. Bed bug bites and flea bites can be tough to tell apart. Health spoke to experts to find out how to differentiate between the two. SCIENCE PHOTO LIBRARY/Getty Images Editor's Note This article contains sensitive medical imagery. What Do Bed Bug Bites Look and Feel Like? Contrary to popular belief, bed bugs—small, flat, reddish-brown insects—don't just live on mattresses; they can be found in the couch and chair seams, curtain folds, and between cushions. Additionally, bed bugs can live in crevices in walls, John Anthony, MD, a dermatologist at Cleveland Clinic, told Health. While bed bugs are found mainly in living areas, it's important to know that their presence isn't determined by the cleanliness of the living conditions where they're located. Bed bugs feed on human blood, but you likely won't notice when they bite. That's because the bugs inject an anesthetic (along with an anticoagulant), so the person doesn't know they're being bitten. "Most people don't feel when the bed bug is biting," said Dr. Anthony. "The bed bugs bite at night, [then] retreat by the time you wake up." Getty Images You'll only realize you've been bitten by bed bugs when small marks appear on your skin. While everyone reacts to bed bug bites differently, bed bug bites, in general, look similar to mosquito bites, with a point in the middle (called a punctum) where the actual bite occurred, Tania Elliott, MD, who works in NYU Langone's Department of Infectious Disease, Allergy and Immunology, told Health. Bed bug bites also have the following characteristics: Welts appear in a line, often one that zigzagsWelts are intensely itchyWelts are typically located on areas of the body that are exposed when you sleep It's also worth noting that bed bug bites can have a purplish color, Dr. Anthony said. Specks of blood on your sheets can also indicate bed bugs. What Do Flea Bites Look and Feel Like? While bed bugs prefer human blood, fleas are tiny insects that prefer to live on cats and dogs. The presence of pets can help you determine if you're dealing with a flea bite or something else. "People mainly get flea bites from pets, so if you have had no pet exposures, it's less likely to be a flea bite," Dr. Elliott said. Fleas will resort to humans if they don't have another option; this can happen if your pet has been away from the house for a while and the flea needs another food source. If your pets are exceptionally itchy, if you see tiny dots on their fur, or if you see tiny insects (which are smaller than bed bugs) on your furniture or other household items, there's a good possibility you have fleas. Getty Images Like bed bug bites, flea bites usually appear as small red dots on the body. They can also resemble mosquito bites, Dr. Anthony said. Symptoms of flea bites include: Bites that appear as three small bumps togetherBites that tend to appear on the feet and anklesItchy bites Risks of Bed Bug Bites and Flea Bites Bed bugs rarely cause complications, but very rarely some people can be allergic to them. Symptoms of an allergy can include enlarged bite marks, painful swellings at the bite site, and, on rare occasions, anaphylaxis—a potentially life-threatening reaction that requires immediate medical attention. Flea bites can develop into a rash called papular urticaria, which manifests as itchy welts that can become hot and painful to the touch. You should not scratch flea bites, as fleas carry bacteria that can lead to infections in humans if the bites become open sores. Infected flea bites can become red, painful, swollen, and full of pus; very rarely, bacteria in fleas carry diseases like typhus and plague, though this is very uncommon in the United States. How to Treat Bug Bites and Flea Bites The best way to treat bites from bed bugs is to apply a topical corticosteroid ointment and/or take an antihistamine for itchiness. Flea bites can be treated with 1% hydrocortisone cream and/or antihistamines. Applying a DEET-based insect repellent can help you ward off flea bites. "The active ingredient in DEET is recommended for effective, long-lasting protection against fleas and other insects," Dr. Elliott said. However, if you have an infestation, you'll need a professional pest control company to come and treat your home with pesticides. If you're unsure of what's causing your symptoms, start by calling your primary care provider or dermatologist, who can help identify the causes and advise you on the next steps. What Does a Tick Bite Look Like? Was this page helpful? Thanks for your feedback! Tell us why! Other Submit 8 Sources Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. MedlinePlus. Bed bugs. Centers for Disease Control and Prevention. Bed bugs FAQ. American Academy of Dermatology Association. Bed bugs: Signs and symptoms. MedlinePlus. Fleas. American Osteopathic College of Dermatology. Flea bites. Centers for Disease Control and Prevention. Bed bugs FAQ, American Academy of Dermatology Association. Bed bugs diagnosis and treatment. MedLine Plus. Fleas.