Snake Bite FAQ

Kyoto: Hiking from Kibune to Kurama

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Five varieties deserve special mention: A single bite from a copperhead is not very dangerous. The diamondbacks (eastern and western species) and the Mojave rattlesnakes deserve attention because they are particularly dangerous. The speckled rattlesnake should also be mentioned because bites from it, like those from the Mojave, may not produce local pain or other reaction. (It is worth noting, however, that Findlay Russell points out that pain is not always associated with an envenomated bite from any variety of snake).

The copperhead has probably the mildest venom of any poisonous snake in the U.S. Adults bitten by a single copperhead usually need only supportive therapy and good cleansing and disinfection of the wound. A study of 400 victims of copperhead bites found only two deaths, both the result of simultaneous bites by three or more snakes. About 3,000 bites a year are inflicted by copperheads. You would probably want to treat a copperhead bite pretty much as any other pit viper bite, but would be able to reassure the patient a bit more and would not be as concerned if medical help were not readily available. This not to say that a copperhead bite won't hurt, it will. These bites are still serious but are unlikely to be life threatening. Gold and Wingert state that "It [antivenin] is unnecessary in most cases of copperhead bite and pygmy rattlesnake bites.

The diamondbacks, on the other hand, are potentially deadly. Both the eastern and western versions are huge, the western species compensating for its slightly smaller size with a more potent venom. MFM lists the eastern diamondback as an aggressive snake and claims it is responsible for more human deaths than any other U.S. snake. Others dispute this. Paul Moler argues it is not particularly aggressive and quotes some numbers which indicate that it is unlikely to kill people.

The Mojave rattler is dangerous in spite of its size. This little rascal is armed with a very potent venom, high in neurotoxins. Pain and other local responses to the bite may be mild, but the systemic response may be marked. Initial reaction is usually mild with severe symptoms coming 12 to 16 hours after the bite. The early symptoms could easily fool one into believing there was no problem. By the time severe symptoms appeared the best time for treatment would have passed. The Mojave rattlesnake also has a couple of close relatives south of the border, the Mexican westcoast rattler and the South American tropical rattlesnake, also known as cascabel or neotropical rattlesnake. They provide problems at least equal to those of the Mojave version.

It is worth mentioning that bites from other North American venomous snakes may yield little local pain, swelling, or other reaction following envenomation. This true of bites from the speckled rattlesnake, Crotalusmitchelli, and possibly also of bites from the rock rattlesnake, Crotalus lepidus, and tiger rattlesnake, Crotalus tigris (Minton,1987). If you know that you have been bitten by one of these snakes, it is probably best to assume that you have been envenomated and procede to a hospital.

Envenomated bites from either the diamondback or the Mojave rattler are serious, possibly even deadly. Do your level best to evacuate the victim quickly to medical facilities.

There is of course a wide variety of poisonous snakes throughout the world. We can't discuss them all here. They are generally confined to warmer climates in places such as Australia, Africa, the Indian subcontinent, and Southeast Asia. Many of these snakes much more dangerous than those native to the North America. There are some exceptions with more northerly ranges. For example, the habitat of the European viper extends to the Arctic Circle. It is not, however, as dangerous as some of the snakes inhabiting warmer climates. If you plan to engage in wilderness activities overseas you should research their venomous snakes.

MFM does have some information on other areas as well as a list of central medical facilities which can provide more information. If you are not familiar with the snakes in an area, assume they are dangerous (especially in warm climates). If you are bitten by an exotic snake in the U.S. (a pet, a zoo specimen, or a research specimen) your physician will want to contact a referral center for information on treatment and antivenin availability. Some such sources include the Antivenin Index in Tucson AZ (602-626-6016), the Oklahoma City Zoo (405-424-3344), the Rocky Mountain Poison Center (303-629-1123), or the New York City Snakebite Emergency Center (718-430-6494).

If your physician desires more information on the two antivenins used for the treatment of North American snakebites, he can contact the manufacturer:

Professional Service
Wyeth-Ayerst Laboratories
PO Box 8299
Philadelphia, PA 19101
(610) 688-4400, or
(800) 950-5099