injuries poisoning
Spider Bites
Key Points
Brown spiders (eg, violin, fiddleback, brown recluse—Loxoscelesspecies) are present in the Midwest and south central US, not in the coastal and Canadian border states. Widow spiders (eg, black widow—Latrodectusspecies) are present throughout the US. Brown spider bites tend to cause pain (sometimes delayed for 30 to 60 minutes), erythema, ecchymosis, and bleb formation, sometimes with surrounding ulceration. Widow spider bites cause immediate pain and sometimes regional or generalized manifestations such as muscle cramping, diaphoresis, hypertension and tachycardia, and weakness. Diagnose spider bites (often falsely suspected by patients) clinically. For brown spider bites, use wound care, local symptomatic measures, and sometimes delayed excision. For widow spider bites, use wound care, local symptomatic measures, and sometimes parenteral opioids, benzodiazepines, and antivenom. 