When to worry about spider bites. Inaccurate diagnosis can have serious, even fatal, consequences.

Almost all species of spiders are capable of biting people, but the bites of only a few are medically significant. Physicians need to be able to recognize the clinical signs and symptoms of common venomous spider bites and administer appropriate therapy. This may be difficult, since the offending spider is rarely seen or recovered for identification. Knowledge of life cycles, habits, and toxicity of venomous spiders enables physicians to provide more comprehensive medical care of bite victims. It is hoped that study of immunologic mechanisms and inflammation mediators will lead to the development of new treatments.