A centipede “bite” is technically an envenomation delivered by specialized, pincer-like front legs called forcipules, not mouthparts. These modified appendages are located near the centipede’s head and inject venom for defense or to subdue prey. The venom contains a mixture of biologically active compounds that primarily cause immediate pain and localized reactions. While most centipede encounters in North America are not life-threatening, the resulting injury can be extremely painful.
Identifying the Injury
The immediate visual appearance of a centipede envenomation is the direct result of the forcipules piercing the skin. The injury typically presents as two small, close-set puncture marks where the modified legs entered the tissue. These marks often form a chevron or inverted V-shape, reflecting the positioning and structure of the forcipules. The size of these twin marks varies depending on the centipede species and its size.
Localized redness develops quickly around the puncture sites. This is usually accompanied by mild to moderate localized swelling as the body reacts to the injected venom. Minor bleeding may occur at the entry points. The presence of the paired puncture marks is a distinguishing feature, although the injury may initially resemble a bee sting.
Understanding Local and Systemic Symptoms
The most prominent and immediate symptom following centipede envenomation is intense, sharp pain, often described as a severe burning sensation. This localized pain starts immediately and can be disproportionately severe compared to the small size of the wound. The discomfort may radiate outward from the site of injury and typically lasts from a few hours up to 48 hours.
Other localized reactions include tingling, numbness, and itchiness around the site. Systemic symptoms, which affect the entire body, are uncommon but possible, especially with larger tropical species or in sensitive individuals. These generalized reactions can include headache, nausea, dizziness, or anxiety. Severe systemic reactions, such as anaphylaxis or cardiovascular effects, are extremely rare exceptions.
Immediate Care and Medical Guidance
Immediate first aid focuses on wound care and pain management. The affected area should be gently washed with soap and water to remove contamination and reduce the risk of infection. Applying a cold compress or ice pack wrapped in a cloth is recommended to reduce swelling and help numb the pain.
Over-the-counter pain relievers, such as acetaminophen or ibuprofen, can be taken to control discomfort and inflammation. Antihistamines may also help manage localized reactions like itching or excessive swelling. Tetanus immunization should be ensured to be up-to-date, as with any puncture wound.
Medical attention should be sought if the pain becomes severe and is not relieved by over-the-counter medications. Professional care is necessary if signs of infection develop, such as increased redness, warmth, or pus, or if red streaks appear near the wound. Any signs of systemic involvement, including persistent vomiting, a rapid heart rate, difficulty breathing, or swelling of the face or throat, require immediate emergency medical evaluation. Children and the elderly may also warrant a physician’s assessment due to their potentially higher sensitivity to the venom.