Preventing and treating rattlesnake bites

Vera Oliphant, a teenager from San Diego, was walking up a hill to find reception on her cell phone when she accidentally stepped into a snake nest hidden under a pile of leaves. She looked down just in time to watch a mother snake and her babies deliver 6 excruciatingly painful bites. She quickly began seeing spots and losing consciousness; thankfully, she was rushed to the hospital and immediately given anti-venom, which saved her life. After four days in the intensive care unit, she was released to rest at home. Her attackers? Rattlesnakes, the deadliest snakes in North America!

Rattlesnakes, water moccasins (“cottonmouths”), and copperheads are reptiles of the family Viperidae, subfamily Crotalinae (formerly Crotalidae), which consists of 18 genera and 151 species. Crotilinae are responsible for most of the 5,000 snake bites reported annually in the United States. They are commonly known as pit vipers, a reference to the heat sensing pits located behind their nostrils. Ranging in size from 12 inches to 12 feet, they live throughout the continental United States and are native to every state except Alaska, Hawaii, and Maine. They normally inhabit desert areas, but are also found in woodland terrain and mountains. Pit vipers seek out shade during the day, preferring to come out at night when it gets cooler. They stick close to areas where they can easily reach shelter, such as heavy brush, rocks, fallen trees, and soil or sand.

Most snake bites occur in the summer months when both snakes and humans are most active outdoors, with the greatest number of venomous bites occurring in southern and western states with warmer climates. Pit vipers tend to leave humans alone, usually striking only after being harassed or startled. That fact is reflected in bite statistics, which demonstrates that men are more frequently bitten than women and that the most common bite locations are the hands (HELPFUL HINT: Do NOT pick-up a rattlesnake!).

While experienced hikers and outdoorsmen will sometimes hear the characteristic warning rattle, often they get bitten after unknowingly walking through a snake’s hiding place. Great care should be taken when walking through tall grass, the woods, or dead leaves, since these are all favorite resting spots for snakes. Wearing thick long pants with boots can help protect your exposed legs in the event that you run into one.

Vera’s experience reflects the diversity of symptoms that can arise following a bite from a pit viper. Common local effects at the site of the bite are pain, bruising, and swelling. Systemic effects range in severity and include non-specific findings such as vomiting, diarrhea, sweating, and weakness, as well as organ-specific damage to kidneys and nerves which could lead to numbness, muscle spasms, and seizures.

So, what do you if you get bitten by a snake?

• First, remain calm. Around 25-50% of pit viper bites are “dry” bites, meaning that the snake does not inject any venom when its fangs pierce your skin. However, if envenomation does occur, getting anxious will only make your heart beat faster, hastening the spread of venom throughout the body.
• Call for help as soon as possible.
• Don’t try to capture or kill the snake; snakes can strike more than once and their fangs can contain venom even after their heads are cut off!
• Try to remember the color and shape of the snake (or take a photo), as that can be helpful for doctors in selecting the appropriate treatment.

While you wait, you should keep the bitten body part at the level of your heart. Do not try to suck out the poison, as that will cause the poison to spread to your mouth; additionally, our mouths are full of bacteria that could cause a serious infection if introduced into the bite wound. Refrain from tying a tourniquet around the affected limb, which will cut off circulation to the limb and concentrate all the venom in one place, leading to increased local tissue death (and the possible need for amputation). When you get to the hospital you will be given anti-venom, which should inactivate the snake’s venom.

If you are bitten by a snake and want professional help, you can speak with a medical toxicologist at a United States regional poison control center by calling 1-800-222-1222.