Spider bites, also known generally as arachnidism, and specifically as loxoscelism when due to Loxosceles (brown recluse), or ladrodectism when due to Latrodectus (black widow), have a wide variety of clinical presentations.
The black widow bite is the site of increasing pain, which can become generalized but there is little to see other than puncta. While the bite of the brown recluse spider can produce severe systemic involvement with pyrexia, malaise, and multi-system evidence of intravascular coagulation, such involvement is rare. Local reactions are more predominant and consist of a central zone of pain, pallor and necrosis, surrounded by a broad halo of erythema. The ulcer heals very slowly.
- High dose glucocorticoids have been advocated for brown recluse spider bites.
- Heparin is therapy for disseminated intravascular coagulation, should that occur.