In the United States, poisonous snakes bite more than 15,000 dogs and cats each year. If your pet has been bitten, a member of the "pit viper" family is most likely the culprit. This type of snake includes the rattlesnake, copperhead and water moccasin. They have broad triangular heads with elliptical pupils, prominent curving fangs and a deep pit located between the nostril and the eye (thus the term "pit viper.")

If your pet has been bitten, you should see a veterinarian immediately. The amount of venom injected varies, and there is no way to tell how much venom may be circulating in your pet. About 50 percent of venom strikes are serious enough to be a medical emergency; 20 percent won't contain any venom at all.

Rattlesnake bites comprise about 80 percent of all bites, and are the most dangerous of the pit vipers. Most bites occur in the southwestern and southeastern part of the United States – Arizona, Georgia, Florida, Alabama, South Carolina and Texas have the highest incidence of fatal bites.

Bites tend to occur when pets are playing in a snake-infested area, and snakebites are usually triggered by your pet's aggressive, playful or curious behavior. Dogs are more likely to be attacked, with most of the strikes hitting the legs or head, especially the muzzle. If your pet is bitten, it is important to keep him calm. Limiting his activity may reduce the effect of the bite.

What to Watch For

The risk of toxicity depends on the type of snake, the size of the animal bitten and the amount of venom injected. Look for:

Rapid swelling at the site of the bite

Intense pain

Oozing blood

Fang marks

Drooling

Rapid breathing

Dilated pupils

Pale gums

Weakness

Collapse

After a snakebite, do not apply a tourniquet, which can affect the circulation and seriously hurt the tissue but do little to stop the circulation of the venom. And don't try to suck the venom out of the bite; human saliva contains many bacteria and may result in severe infection. In addition, do not try to give your pet any pain medications, tranquilizers or ice treatments.

Veterinary Care

Diagnosis is based on a physical exam to look for evidence of a snakebite, as well as the potential exposure to venomous snakes. Blood work may be done to evaluate how long it takes for your pet's blood to coagulate. Longer coagulation times can indicate the presence of venom.

Treatment depends on which species of snake bit your pet, as well as the signs of toxicity displayed by the pet. You can expect to hospitalize your pet in severe cases.

Antivenin is recommended for rattlesnake bites. However, antivenin is a human product, and availability may be limited in certain parts of the country. (Antivenin is rarely needed for copperhead bites.) Your veterinarian may give your pet diphenhydramine (Benedryl) to reduce allergic reactions associated with the snakebite. Your pet will also be treated for pain and infection.

Prevention

Avoid areas where snakes are likely to inhabit. Snakes prefer to live in quiet and dark areas, such as woodpiles. If your pet has recovered from a snakebite, it is very important to make sure he isn't bitten again; future venomous bites may result in much more severe toxic signs and can cause death.