Clinical Review

Bite of the Brown Recluse Spider

Author and Disclosure Information



Daily wound checks should be performed until the lesion is noted to be improving or no longer worsening. At each follow-up for the initial 72 hours, it is recommended that patients undergo a CBC, including platelet level, to detect progression of the infection or systemic involvement, and urinalysis to check for hematuria. Renal function should be monitored as needed.1,2

Patient Education
Regarding brown recluse spider bites, patients should be advised to keep five points in mind:

• Diagnosis is made by confirmation that the spider is a brown recluse, ideally with the capture and expert evaluation of the spider22

• Workup will focus on history, geographic locale, and environ of patient when supposed bite occurred4,7,8

• Treatment varies but may include a tetanus shot, antibiotics, dapsone, steroids, hyperbaric oxygen therapy, and in severe cases of necrosis, surgery1,2,7,19,20

• Follow-up will occur routinely during the initial 72 hours1,2

• Prevention of bites includes avoiding piles of clutter in garages, sheds, and under beds; and wearing long sleeves when working in these areas.12

Finally, because the venom of the brown recluse spider is poisonous, the NIH encourages exposed persons to contact the National Poison Control Center at (800) 222-1222.23

Brown recluse spider bites, though most likely overdiagnosed, do occasionally occur in areas where the creature is endemic. However, a brown recluse spider bite should be considered a diagnosis of exclusion and other possibilities considered first in light of their limited presence in North America and their nonaggressive nature.

Any patient who calls to report a suspected brown recluse spider bite should be instructed to bring the spider to the office, if possible, for identification. The spider should then be identified with certainty as a brown recluse by the appropriate expert so that treatment for the patient can be based on a correct diagnosis rather than one of presumption.

Next Article: