Pit vipers, such as the rattlesnake, copperhead, and cottonmouth(also called water moccasin), are poisonous (venomous) snakes. They leave one, two, or three puncture marks on the skin, but you won't always see any marks.
Symptoms of a pit viper snakebite usually appear within a few minutes to a few hours after a bite and may include:
Severe, immediate pain with rapid swelling.
Bruising of the skin.
Trouble breathing.
Changes in heart rate or rhythm.
A metallic, rubbery, or minty taste in the mouth.
Numbness or tingling around the mouth, tongue, scalp, feet, or the bite area.
Swelling in lymph nodes near the bite.
Signs of shock.