Fast Five Quiz: Bites and Stings

Richard H. Sinert, DO


April 29, 2019

Admission to the hospital is generally indicated after widow spider bite for the following patients (subject to clinical judgment):

  • Severely symptomatic children

  • Pregnant women

  • Patients with a history of hypertension or heart disease

  • Patients with intractable pain and contraindications to antivenom

  • Patients with unusual complications of envenomation

  • Patients who develop anaphylaxis to antivenom

Treatment of brown recluse envenomation is directed by the severity of the injury. General wound management consists of local debridement, elevation, and loose immobilization of the affected area.

Because the activity of sphingomyelinase D, the major toxin in brown recluse venom, is temperature dependent, application of local cool compresses is helpful and should be continued until progression of the necrotic process appears to have stopped. Other treatments such as colchicine, steroids, antivenom, nitroglycerin patches, and surgical excision have been reported, but insufficient data exist to support their clinical use today.

In general, do not administer antivenom in the field because of the risk for severe allergic complications.

Dapsone has been recommended by authorities to treat some local lesions because of its leukocyte-inhibiting properties. However, because of the potential for adverse effects associated with dapsone use, appropriate caution should be exercised. For example, no well-controlled studies have shown dapsone to affect clinical outcome in human brown recluse envenomations; therefore, it is not routinely recommended for all spider bites. Dapsone is approved for use in children after appropriate evaluation, beginning at doses of 1 mg/kg every 24 hours.

Read more on the treatment of widow spider bites.


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