Rattlesnakes are Waiting For Your Dog

It is that time of year when rattlesnakes are out in wooded and not so wooded areas around Laguna Niguel. It is also the time of year where we spend more time outdoors with our pets in the snake’s environment.  

We have between seven and eight species of poisonous snakes in California. They are all in the family Crotalidae or rattlesnakes. The physical appearance of the various rattlesnake species is variable and it is difficult to tell which species you are looking at.

Most bites to dogs occur on the face or extremities. The bite of the rattlesnake is generally hemotoxic, which means it affects the integrity of the blood vessels. Swelling can be very dramatic. The venom also disrupts normal blood clotting mechanisms leading to uncontrolled bleeding. This blood loss can lead to shock and death. Facial bites can lead to throat swelling and impaired breathing.  An exception would be the Mojave rattlesnake which produces neurotoxin venom. This causes rapid paralysis, particularly of reparatory muscles. 

The severity of a snake bite depends on multiple factors:

• The species of snake  
• The location of the bite
• The amount of venom injected
• The size of the dog

Immediate treatment for rattlesnake bites is imperative in saving the life of the dog. The quicker the bite is recognized, the more effective the treatment will be. Do not try to cut the bite wound or suck venom out of the bite site. Seek veterinary treatment immediately, no matter what time of day.

Since circulatory collapse is the most common cause of death, Intravenous fluid support and blood pressure monitoring is of utmost importance. Hospitalization and fluid support with testing of laboratory values for a minimum of 24 hours is recommended. Antivenin is available for dogs. There are two types available and they are an extremely important part of therapy. They are also very expensive, with each vial being approximately $700 to $1,000 and multiple vials may be needed.  

Antihistamines may or may not be helpful for the snake bite, but can decrease an allergic reaction to the antivenin. Corticosteroids would seem to be logical to reduce inflammation, but have been shown in studies to be contraindicated. Occasional blood transfusions may be needed to control life threatening blood loss.  Antibiotics are commonly used to prevent secondary infection.

A rattlesnake vaccination is available but is controversial. It does not mean that a dog that is vaccinated will not need treatment or necessarily survive a rattlesnake bite. The manufacturer says that it will decrease the severity of the bite. The University of California, Davis, School of Veterinary Medicine says: “based on the existing evidence we do not currently recommend routine vaccination for dogs for rattlesnake envenomation, and the vaccine is not stocked by our pharmacy.” 

There are currently multiple rattlesnake aversion training courses available from multiple trainers. The effectiveness of these programs is variable and should not be relied on to protect your dog.

I hope this will not discourage you and your dog from going out and enjoying a great walk on the trails or fields of Laguna Niguel, but rather increase your awareness to avoid snakes and what to do in case your dog is bitten. Make sure your veterinarian has antivenin on his premises at all times and be aware that our local emergency clinic is open after your veterinarian is closed and does have antivenin available. Remember time is of the essence for a successful outcome.