First aid: Snakebites
Most North American snakes aren't poisonous. Some exceptions include the rattlesnake, coral snake, water moccasin and copperhead. Their bites can be life-threatening.
Of the poisonous snakes found in North America, all but the coral snake have slit-like eyes and are known as pit vipers. Their heads are triangular, with a depression (pit) midway between the eye and nostril on either side of the head.
Other characteristics are unique to certain poisonous snakes:
To reduce your risk of snakebite, avoid touching any snake. Instead, back away slowly. Most snakes avoid people if possible and bite only when threatened or surprised.
If a snake bites you
Call 911 or seek immediate medical attention, especially if the area changes color, begins to swell or is painful.
Last Updated: 2012-04-18
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