Centipedes are predatory arthropods that can inflict a painful injury, though the term “bite” is technically inaccurate for the mechanism they use. These multi-legged creatures (class Chilopoda) are generally not aggressive toward humans. They only strike defensively when they feel threatened, such as when accidentally handled or pressed against the skin. Understanding the delivery method and potential symptoms guides appropriate care.
How Centipedes Deliver Their Venom
Centipedes do not use their mandibles or mouthparts to inflict injury. Instead, they possess modified front legs called forcipules, which function as venom-injecting claws. These appendages are located just behind the head and curve forward, resembling sharp pincers. The forcipules contain a gland that produces venom, delivered through a small pore near the tip of each claw. This action pierces the skin and injects the venom, creating an injury clinically viewed as a sting or envenomation rather than a true bite. The injury often appears as two distinct puncture marks arranged in a V-shape.
Symptoms and Severity of a Centipede Injury
The symptoms following a centipede envenomation vary depending on the species and the amount of venom injected. For most common household species, the injury is generally mild, with localized effects comparable to a bee sting. These effects typically include immediate, sharp pain at the site, followed by redness and swelling.
The localized reaction may also involve a burning sensation, itchiness, and numbness or tingling around the puncture marks. These symptoms are usually short-lived, often resolving within a few hours to a couple of days. The venom contains a complex mixture of chemical substances, including histamine, which contributes to the pain and inflammation.
Larger, tropical species, such as the Giant Desert Centipede, deliver a more substantial dose of venom, resulting in intense, prolonged pain. Injuries from these larger species may rarely cause systemic symptoms felt throughout the body, including headache, nausea, or localized tissue necrosis. Though fatalities are rare, a severe allergic reaction (anaphylaxis) remains a possibility for any venomous injury.
Seek medical attention immediately if systemic symptoms develop, such as difficulty breathing, swelling of the face or throat, or widespread hives. A doctor should also be consulted if localized pain and swelling do not improve within 48 hours, or if signs of a secondary infection appear.
Immediate Care and Keeping Centipedes Away
Immediate care for a centipede injury focuses on cleansing the wound and managing the local reaction. The puncture site should be washed immediately with soap and water to prevent infection. Applying a cold compress or an ice pack wrapped in a cloth helps reduce swelling, inflammation, and pain.
Over-the-counter pain relievers or antihistamines can be used to manage discomfort and reduce any allergic response. It is advised not to use a warm compress, as heat can intensify the symptoms associated with the venom. Most uncomplicated injuries heal completely within a few days with this simple first aid.
To minimize encounters, make the home environment less appealing to centipedes, which thrive in moist, dark conditions. Reducing moisture involves using dehumidifiers, repairing leaky plumbing, and ensuring proper ventilation. Centipedes are also drawn by the presence of other pests, so controlling their food source, such as spiders and insects, can deter them.
Physical exclusion is a powerful preventive measure, requiring homeowners to seal cracks and gaps in the foundation, walls, and around windows and doors. Removing clutter and debris from the interior and perimeter of the house eliminates their preferred hiding spots. This includes clearing leaf litter, wood piles, and excess storage near the foundation.