In this Article

• Introduction to snake bites
• What are the symptoms of a poisonous snake bite?
• What is appropriate first aid for poisonous snake bites?
• How are poisonous snake bites treated?
• Snake Bites Glossary
• Snake Bites Index
• Find a local Doctor in your town

What is appropriate first aid for poisonous snake bites?

If someone is bitten by a poisonous snake, the bitten area should be immobilized and the victim transported to a hospital as quickly as possible. The bitten area should be washed with soap and water. A wide constriction bandage (tourniquet) may be applied two to four inches upstream of the bitten area (if on an extremity) so long as the pressure is not too tight (one or two fingers should be able to slide under the band). Overly tight tourniquets should never be used as these can block arterial blood flow to the affected area and worsen tissue damage.

Incising (cutting) and suctioning the bite area has not been shown to be beneficial, but a venom extractor (found in commercial snake bite kits) may be helpful if it is applied to the area within five minutes of the bite and left in place for 30 minutes. A 2004 study of mock venom extraction using a suction device, however, questioned the validity of venom extractors and suggested that their use is unlikely to be effective.

Ice or cooling packs should never be applied to the area as these may result in greater harm, and incisions of the bitten area are also potentially harmful and have no benefit.

Most importantly, any victim of a venomous snake bite should be evaluated in an emergency medical care facility as soon as possible.

How are poisonous snake bites treated?

Treatment of poisonous snake bites involves thorough cleansing of the wound and observation of the victim to determine whether symptoms suggestive of evenomation develop over time. In most cases of poisonous snake bites, an antivenin (also called antivenom) is given, preferably by intravenous administration. For rattlesnake, cottonmouth, and copperhead (pit viper) bites, Antivenin (Crotalidae) Polyvalent (ACP) equine (horse)-derived antivenin was the standard treatment in emergency departments for many years. ACP, however, is known to cause a number of potentially severe allergic reactions because of its equine origin. In 2000 the U.S. FDA approved the sheep-derived antivenin CroFab which appears to have a lower incidence of associated allergic reactions, although clinical trials comparing the two have not been performed.

References: Juckett, G and Hancox JG. Venomous Snakebites in the United States: Management Review and Update. American Family Physician 65(7), 2002.

FDA Consumer Magazine. For Goodness Snakes- Treating and Preventing Poisonous Snake Bites. Revised 2002.

Lavonas EJ; Gerardo CJ; O'Malley G; Arnold TC; Bush SP; Banner W Jr; Steffens M; Kerns WP 2nd. Initial experience with Crotalidae polyvalent immune Fab (ovine) antivenom in the treatment of copperhead snakebite. Ann Emerg Med 2004 Feb;43(2):200-6.

Alberts MB; Shalit M; LoGalbo F. Suction for venomous snakebite: a study of "mock venom" extraction in a human model. Ann Emerg Med 2004 Feb;43(2):181-6.