Recently at our REI Lectures on “Wilderness First Aid for Dogs”, we have been receiving many inquiries regarding antivenom and the rattlesnake vaccine. To provide more insight, one of our long time ER Doctors, Dr. Mary Ellen Finely of SAGE Redwood City will break down the difference.
Antivenom is a purified antibody or antibody fragment aka a protein that will inactivate the rattlesnake venom in the body. There are many years of hard science and excellent controlled studies behind this product. Most dogs that have been bitten should receive antivenom. It is an injection given intravenously over 30-60 minutes and the pet MUST be monitored closely by a team of veterinary professionals during this time. Fortunately with newer antivenoms reactions are rare!
The rattlesnake vaccine is a subcutaneous (under the skin) injection of a small amount of inactivated venom. In theory, this stimulates the pet to produce their own antibodies and thus be able to neutralize venom quickly in the event of a bite. There are no controlled studies that show that the vaccine is effective and there are reports of severe (although infrequent) vaccine reactions. Because of this the vaccine is not routinely recommended.
There is some anecdotal evidence that the vaccine may delay reaction time slightly, however it is not a substitute for treatment. The vaccine should be considered only in pets that are frequently in very remote areas with high snakebite potential.
IMPORTANT TO NOTE: If the pet is bitten and has been vaccinated with the rattlesnake vaccine, the pet still needs to be treated right away by a veterinarian.