House centipedes are not dangerous to humans. These fast-moving, many-legged arthropods look alarming, but their venom is designed for insects and other small prey, not people. Their fangs are typically too small and weak to break human skin, and on the rare occasion they do bite, the result is comparable to a mild bee sting.
Why House Centipedes Rarely Bite
Centipedes deliver venom through a pair of modified front legs called forcipules, which have evolved from walking legs into rigid, fang-like piercing structures. Near the tip of each forcipule sits a small opening connected to a venom gland. In larger tropical centipedes, these structures are reinforced with metals like zinc and calcium, making them strong enough to puncture skin easily. House centipedes, however, are small (usually under two inches long), and their forcipules lack the size and strength to reliably pierce human skin.
House centipedes are also not aggressive. They’re nocturnal hunters that actively avoid contact with people. A bite only happens if you accidentally trap one against your skin, like rolling onto one in bed or pressing it inside clothing. Even then, the centipede is acting defensively, not attacking.
What a Bite Feels Like
If a house centipede does manage to break your skin, you’ll likely feel a brief, sharp sting. Centipede venoms contain serotonin and histamine, both of which trigger immediate pain and local inflammation. The area around the bite may become red, slightly swollen, and itchy, similar to a bee sting or mosquito bite. These symptoms typically resolve within a few hours to a day or two.
Larger centipede species (like the giant desert centipede found in the American Southwest) are a different story. Their venom contains enzymes called metalloproteases that can cause skin damage, blistering, and prolonged swelling. House centipedes don’t deliver enough venom to cause these kinds of effects.
Allergic Reactions Are Rare but Possible
Centipede venoms contain allergenic proteins that can, in rare cases, trigger a significant allergic response. Studies on centipede bites in general (mostly from larger species) have found anaphylaxis rates between 1.5% and 5% of cases. These figures come from bites by much larger tropical centipedes, so the risk from a house centipede is likely far lower. Still, if you notice hives spreading beyond the bite area, difficulty breathing, or facial swelling after any centipede bite, treat it as a medical emergency.
Infection Risk Is Low
The bite wound itself is tiny, but any break in the skin carries some infection risk. Documented cases of serious skin infections following centipede bites have involved common bacteria already living on the person’s skin, particularly staph and strep, entering through the wound. These cases are extremely rare and have been associated with larger centipede species. The practical takeaway: clean any bite promptly and watch for signs of infection like increasing redness, warmth, or pus over the following days.
How to Treat a Bite
If you do get bitten, wash the area thoroughly with soap and water. Don’t use rubbing alcohol. Apply a cloth-wrapped ice pack in cycles of 10 minutes on, 10 minutes off to reduce swelling and pain. An over-the-counter antihistamine can help with itching, and ibuprofen or acetaminophen can manage any lingering pain. Most bites resolve on their own without any medical intervention.
If you’re unsure about the severity, the national Poison Help hotline (1-800-222-1222) can help you decide whether a trip to the emergency room is warranted.
Are They Dangerous to Pets?
House centipedes are not toxic to cats or dogs. Even if your pet catches and eats one, the small amount of venom won’t cause harm. Larger centipede species are a genuine concern for pets, particularly cats. The giant desert centipede, for example, can deliver enough venom to cause drooling, vomiting, difficulty breathing, and in severe cases, seizures. But the common house centipede your cat is batting around the basement is harmless.
They’re Actually Useful to Have Around
House centipedes are voracious predators of pests you’d probably rather not share your home with. Their diet includes cockroach nymphs, silverfish, carpet beetle larvae, spiders, bedbugs, flies, moths, earwigs, and crickets. A single house centipede patrolling your basement or bathroom is quietly doing pest control work for free.
That said, seeing large numbers of house centipedes usually signals a moisture problem or an abundance of the prey insects they’re feeding on. Reducing humidity with a dehumidifier, sealing cracks around foundations and windows, and addressing any underlying pest problem will naturally reduce their numbers. If the occasional lone centipede doesn’t bother you, letting it stay is arguably the more practical choice.