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Evaluation and management of Crotalinae (rattlesnake, water moccasin [cottonmouth], or copperhead) bites in the United States

Steven A Seifert, MD, FAACT, FACMT
Section Editors
Daniel F Danzl, MD
Stephen J Traub, MD
Michele M Burns, MD, MPH
Deputy Editor
James F Wiley, II, MD, MPH


Snake bites are a significant problem in the United States. Successful treatment requires prompt definitive medical evaluation, careful clinical assessment, and timely administration of antivenom in selected patients. Consultation with a medical toxicologist or other clinician with experience in managing poisonous snake bites is recommended prior to antivenom administration. Phone consultation with a medical toxicologist is available through a United States regional poison control center by calling 1-800-222-1222.

The clinical evaluation and management of poisonous Crotalinae (rattlesnake, water moccasin [cottonmouth] or copperhead) snake bites is reviewed here. The principles of management of coral snake bites and snake bites outside the United States are discussed separately. (See "Evaluation and management of coral snakebites" and "Snakebites worldwide: Clinical manifestations and diagnosis".)


Rattlesnakes, water moccasins (cottonmouths), and copperheads are members of the family Viperidae, subfamily Crotalinae (formerly Crotalidae). They are also commonly called pit vipers, a name that refers to the heat sensing pit located behind the nostrils.


Rattlesnakes, water moccasins (cottonmouths), and copperheads are the most numerous and cause the most snake bites in the United States. Elapids (coral snakes) and imported exotic snakes cause a smaller number [1].

Estimates from the 1960s suggest that there were approximately 8000 bites annually from poisonous snake species in the United States, with 10 to 12 deaths annually [2]. Additional studies of rattlesnake bites suggest that there is an increasing number of significant bites, but mortality has remained at low levels since the 1980s [3,4].


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Literature review current through: Jul 2017. | This topic last updated: Dec 02, 2016.
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