Snakebites: First aid

By Mayo Clinic Staff

Most North American snakes aren't dangerous to humans. Some exceptions include the rattlesnake, coral snake, water moccasin and copperhead. Their bites can be life-threatening.

If you are bitten by a venomous snake, call 911 or your local emergency number immediately, especially if the area changes color, begins to swell or is painful. Many emergency rooms stock antivenom drugs, which may help you.

If possible, take these steps while waiting for medical help:

  • Remain calm and move beyond the snake's striking distance.
  • Remove jewelry and tight clothing before you start to swell.
  • Position yourself, if possible, so that the bite is at or below the level of your heart.
  • Clean the wound, but don't flush it with water. Cover it with a clean, dry dressing.
  • Don't use a tourniquet or apply ice.
  • Don't cut the wound or attempt to remove the venom.
  • Don't drink caffeine or alcohol, which could speed your body's absorption of venom.
  • Don't try to capture the snake. Try to remember its color and shape so that you can describe it, which will help in your treatment.

Most snakebites occur on the extremities. If the bite is from a nonvenomous snake, typical symptoms are pain and scratches at the site.

Usually, after a bite from a poisonous snake, there is severe burning pain at the site, within 15 to 30 minutes. This can progress to swelling and bruising at the wound, and all the way up the arm or leg. Other symptoms include nausea and a general sense of weakness, as well as an odd taste in the mouth.

Some snakes, such as coral snakes, have toxins that cause neurological symptoms, such as tingling, difficulty speaking and weakness.

Most venomous snakes in North America have eyes like slits and are known as pit vipers. Their heads are triangular with a pit between the eye and nostril on either side of the head.

Other characteristics are unique to certain venomous snakes:

  • Rattlesnakes rattle by shaking the rings at the end of their tails.
  • Water moccasins' mouths have a white, cottony lining.
  • Coral snakes have red, yellow and black rings along the length of their bodies. Their heads aren't triangular and the pupils are round.
  • Copperhead snakes have a copper-colored head and reddish brown bodies with dark bands.
Aug. 16, 2017