Snakebite 101

There is an abundance of advice on the internet describing a variety of first aid techniques to employ if your pet is bitten by a snake. Some include cutting over the bite site and sucking out the venom, using a snakebite kit, applying a tourniquet, applying ice packs, and administering antihistamines and antibiotics. NONE of these treatments work and only serve to delay effective treatment. Delayed treatment can result in more severe clinical signs and, sometimes, contribute to fatality. Pets bitten by a rattlesnake need to be evaluated by a veterinarian immediately so that antivenom can be administered if appropriate.

Rattlesnake venom is a mix of more than a dozen enzymes that can cause tissue necrosis, blood clotting disorders circulatory collapse, and neurologic signs, The chemical makeup of venom varies depending on the age and sex of the snake, geographic location, time of year, and how long since the snake last released venom.

The cornerstone of treatment for rattlesnake bites is antivenom.  It binds to the venom and removes it from circulation. Early treatment is most effective while venom is circulating in the bloodstream.  Antivenom is administered intravenously by a veterinarian. It is expensive but it can be lifesaving.  Several antivenom products are available – your vet will utilize a specific antivenom based on your pet’s clinical signs and snake prevalence in your area.

Pets are commonly bitten on the face and legs as they explore under shrubbery or rocks. Fang marks may or may not be visible (Fangs cause tiny puncture marks that can be hard to find on a furry pet). Often localized bruising and swelling are the first clinical signs. The bites are very painful and animals can bite when Owners attempt to examine the area – Be careful! Animals can become weak and collapse quickly. They may have rapid breathing, sometimes vomit, and can have muscle tremors. Small dogs and cats are more likely to develop severe signs.

If you witness your pet bitten or suspect a snakebite please bring your pet to your vet immediately even if you do not see any concerning clinical signs. The external signs of a snake bite can be delayed for hours but that animal may still need antivenom immediately.

Rattlesnakes can bite without injecting venom. This is called a ‘dry bite’. Dry bites occur when a snake has recently released venom or is giving a warning bite. Approximately 20-25 percent of bites are dry; 30 percent of bites are mild meaning they cause local pain and swelling in the bite area and no systemic symptoms; 40 perfect of bites are severe with approximately five percent being fatal. Your vet can perform blood tests to distinguish between an envenomation and a dry bite.

Pets that are envenomated often require hospitalization for fluid support and pain management in addition to antivenom. Sometimes other treatments including laser therapy and hyperbaric oxygen therapy help speed recovery.

A rattlesnake vaccine is available, however, there are no published studies that document the efficacy of this vaccine. This vaccine may lessen clinical signs but may not completely protect a pet from the effects of the venom. Even vaccinated pets should be examined by a veterinarian promptly when a rattlesnake bite is witnessed or suspected.

If you witness or suspect a snakebite try to stay calm and keep your pet calm. If possible, keep the bite site lower than the heart. Cover your pet’s face with a thick towel so you can safely transport him to the vet. If the bite is on the face remove your pet’s collar if you can do so safely. Call ahead to your vet’s office to alert them to the situation and be sure they have antivenom in stock.

The best approach to snakebites is prevention. Walk away when you hear the rattle!  Keep dogs on leash when hiking and stay on open trails. Do not allow pets outside unsupervised. Keep grass mowed short and keep your dog away from woodpiles. Most rattlesnake bites occur after 2pm; limiting activity to early in the day decreases but does not eliminate the risk of snakebite. Some trainers offer rattlesnake aversion training for dogs – this can be another tool to help your dog make a good decision should it discover a… snake in the grass!