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Management of widow spider bites

Richard S Vetter, MS
David L Swanson, MD
Julian White, AM, MB, BS, MD, FACTM
Section Editors
Stephen J Traub, MD
Daniel F Danzl, MD
Deputy Editor
James F Wiley, II, MD, MPH


This topic will review the management of widow spiders (genus Latrodectus) bites. Clinical manifestations, diagnosis, and differential diagnosis of widow spider bites, recluse spider bites, and an overview of the approach to a suspected spider bite are discussed separately. (See "Clinical manifestations and diagnosis of widow spider bites" and "Bites of recluse spiders" and "Approach to the patient with a suspected spider bite: An overview".)


The severity of widow spider bite envenomation is divided into three grades as follows:

Mild envenomation – Mild widow spider envenomation consists of local skin irritation that may also be associated with local muscle pain and spasms adjacent to the bite.

Moderate envenomation – Generalized spasmodic muscle pain in the bitten extremity, sometimes involving the back, chest, or abdomen, and accompanied by local diaphoresis constitutes the common manifestations of moderate envenomation.

Severe envenomation – Severe envenomation causes pain that is severe and difficult to control or accompanied by systemic findings such as tachycardia and hypertension, nausea and vomiting, or headache.

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Literature review current through: Oct 2017. | This topic last updated: Oct 06, 2017.
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