Topic Overview
Poisonous snake or lizard bite
A bite from a
poisonous (venomous) snake or lizard requires emergency care. If you have been
bitten by a snake or lizard that you know or think might be poisonous,
call 911 or other emergency services immediately. Do not wait for symptoms to
develop.
If you are not sure what type of snake or lizard bit you,
call the Poison Control Center immediately to help
identify the snake or lizard and find out what to do next. Medicine to
counteract the effects of the poison (antivenom) can save a limb or your
life.
It is important to stay calm.
Poisonous snakes or lizards found in North America include:
Maine, Alaska, and Hawaii are the only states that don't
have at least one poisonous snake species in the wild.
Poisonous snakebite
Symptoms of a pit viper snakebite often appear from minutes to hours after a bite. Severe
burning pain at the site usually begins within minutes, and then swelling
starts spreading out from the bite.
Things that affect the
severity of a poisonous snake or lizard bite include the:
- Type and size of the snake or
lizard.
- Amount of venom injected (if any).
- Potency of
the venom injected.
- Location and depth of the
bite.
- Number of bites and where they occurred on the
body.
- Age, size, and
health of the person who was bitten.
If you do not develop symptoms within 8 to 12 hours, it
is possible that no venom was injected; this is called a dry bite. At least
25%, and perhaps up to 50%, of bites are dry. If poison is released in the bite,
about 35% of the bites have mild injections of poison (envenomations), 25% are
moderate, and 10% to 15% are severe.
It is important to remember
that a snake only injects part of its venom with each bite, so it is still
dangerous after the first strike. A bite from a young snake can be serious. And
a dead snake, even one with a severed head, can still bite and release venom by
reflex action for up to 90 minutes after it dies. Even if you do not develop
symptoms within 8 hours, continue to watch for symptoms for 2 weeks or more.
Nonpoisonous snake or lizard bite
Most snakes and
lizards in North America are not poisonous. Bites may be frightening, but most
do not cause serious health problems. A bite from a small nonpoisonous snake
might leave teeth marks, a minor scrape, or a puncture wound without other
symptoms. Home treatment often relieves symptoms and helps prevent
infection.
Although most nonpoisonous snakebites can be treated at
home, a bite from a large nonpoisonous snake (such as a boa constrictor,
python, or anaconda) can be more serious. In North America, these snakes are
found in the Florida Everglades and zoos, but they may also be kept as exotic pets. The force of the
bite can injure the skin, muscles, joints, or bones. Other problems can occur
with a nonpoisonous snake or lizard bite even if the reptile is small. A snake
or lizard's tooth may break off in a wound or a
skin infection may develop at the site of the
bite.
Check your symptoms to decide if and when
you should see a doctor.
Check Your Symptoms
Home Treatment
Poisonous snake or lizard bite
If you were bitten by
a snake or lizard that you know or think is poisonous, call 911 or other emergency services immediately. Do not wait for symptoms to develop.
Symptoms may progress from mild to severe rapidly.
If you are not
sure what type of snake or lizard bit you, take a picture of it. But do not do
this if it will delay treatment or put someone at risk for more bites. Do
not waste time or take any risks trying to kill or bring in the snake. Only
trap a poisonous snake if the chances are good that it will bite more people if
you let it go. It is important to remember that a snake only injects part of
its venom with each bite, so it can still hurt you after the first strike. And
a dead snake, even one with a severed head, can bite and release venom by
reflex action for up to 90 minutes after it dies.
Medicine (antivenom) to counteract the effects of the poison can
save a limb or your life. Antivenom is given as soon as a doctor determines it
is needed, usually within the first 4 hours after the snakebite. Antivenom may
be effective up to 2 weeks or more after a snakebite.
Immediate home treatment
Immediate home treatment
should not delay transport for emergency evaluation.
- If you think the snake bite is an emergency, call 911.
- Remain calm and try to rest
quietly.
- If you are not sure what type of snake or lizard bit you,
call a Poison Control Center immediately to help
identify the snake or lizard and find out what to do next.
- Remove any
jewelry. The limbs might swell, making it harder to remove the jewelry
after swelling begins.
- Use a pen to mark the edge of the swelling
around the bite every 15 minutes. This will help your doctor estimate how the
venom is moving in your body.
Avoid these treatment measures
Avoid doing anything
that might cause more problems with the snake or lizard bite.
- Do not cut the bite
open.
- Do not suck on the bite wound or use
any kind of extraction device.
- Do not use a
constriction band, such as a tourniquet or bandage, on a
bite.
- Do not soak your hand or foot in ice
water or pack your arm or leg in ice. This can increase damage to the skin and
cause a cold-induced injury, such as frostbite.
- Do not raise the bitten arm or leg above your head. This may increase the
flow of venom into the bloodstream.
- Do not drink alcohol.
- Do not give any
prescription or nonprescription medicines after a poisonous snake or lizard
bite unless your doctor tells you to. Some medicines, such as aspirin,
ibuprofen, or naproxen, may cause increased bleeding.
Nonpoisonous snake or lizard bite
If you are certain
the snake or lizard was not poisonous, use home treatment measures to reduce
symptoms and prevent infection.
- Use direct pressure to stop any bleeding.
- Look at the wound to make sure a snake or
lizard tooth is not in the wound. If you can see a tooth, remove it with
tweezers, taking care to not push it farther into the wound.
- Clean
the bite as soon as possible to reduce the chance of infection, scarring, and
tattooing of the skin from dirt left in the wound. Wash the wound for 5 minutes
with large amounts of warm water and soap (mild dishwashing soap, such as
Ivory, works well).
- Do not use rubbing alcohol, hydrogen
peroxide, iodine, or Mercurochrome, which can harm the tissue and slow wound
healing.
- Soak the wound in warm water for 20 minutes, 2 to 4 times
a day, for the next 4 to 5 days. The warmth from the water will increase the
blood flow to the area, which helps reduce the chance of
infection.
- Puncture wounds usually heal well and may not need a
bandage. You may want to use a bandage if you think the bite will get dirty or
irritated.
- Clean the wound thoroughly before putting
the bandage on it.
- Apply a clean bandage when it gets wet or
soiled. If a bandage is stuck to a scab, soak it in warm water to soften the
scab and make the bandage easier to remove.
- If available, use a
nonstick dressing. There are many bandage products available.
- Be
sure to read the product label for correct use.
- Use of an antibiotic ointment has not been shown
to affect healing. If you choose to use an antibiotic ointment, such as
polymyxin B sulfate (for example, Polysporin) or bacitracin, apply the ointment
lightly to the wound. The ointment will keep the bandage from sticking to the
wound. If a skin rash or itching under the bandage develops, stop using the
ointment. The rash may be caused by an allergic reaction to the
ointment.
- Determine whether you need a
tetanus shot.
- An
ice or cold pack may help reduce swelling and bruising. Never apply ice
directly to a wound or the skin. This could cause tissue damage.
Medicine you can buy without a prescription| Try a nonprescription
medicine to help treat your fever or pain: |
|---|
- Acetaminophen, such
as Tylenol
- Do not use a nonsteroidal
anti-inflammatory drug, such as Advil, Motrin, Aleve, or aspirin.
|
Safety tips| Be sure to follow
these safety tips when you use a nonprescription medicine: |
|---|
- Carefully read and follow all
directions on the medicine bottle and box.
- Do not take more than
the recommended dose.
- Do not take a medicine if you have had an
allergic reaction to it in the past.
- If
you have been told to avoid a medicine, call your doctor before you take
it.
- If you are or could be pregnant, do not take any medicine other
than acetaminophen unless your doctor has told you to.
|
Symptoms to watch for during home treatment
Call your doctor if any of the following occur during home
treatment:
Prevention
Snakebites are more likely to occur in
warm-weather months when both snakes and people are more active outdoors. Most
snakebites occur on the fingers, hands, and arms when someone is working with
or trying to catch a snake. The legs and feet are also common bite sites; these
bites usually occur when a person (especially a child or a hiker) accidentally
disturbs a snake.
Snakes and lizards are popular exotic pets, so
the risk for being bitten has increased.
Many snake and lizard
bites can be prevented.
- Find out what local snakes and lizards are found
in your area. Learn what they look like, whether they are poisonous, and where
you are most likely to see them.
- If you see a snake or lizard, do
not bother it. Keep in mind that the striking range of a snake is about
two-thirds of its length.
- Do not pick up or handle snakes. Even a
dead snake can bite and release venom through reflexes for 90 minutes or more
after it dies.
- Watch for snakes around wood or rock piles or caves.
Wear protective shoes, boots, and clothing when you are hiking, camping,
fishing, and hunting.
- Do not drink alcohol or use illegal drugs
while doing outdoor activities where you might encounter a snake. The effects
of the alcohol and drugs may slow your judgment and reflexes.
- If
you have a pet snake or lizard or are thinking about getting one, learn how to
handle it safely to avoid being bitten. Find out what first aid supplies you
will need if you are bitten, and have them handy.
If you are often in an area where there are poisonous snakes,
consider carrying a first aid kit. Carry a cellular phone, if you have one, to
call for help if you are bitten.
Preparing For Your Appointment
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Questions to prepare for your appointment
You can help your
doctor diagnose and treat your condition by being prepared to answer the
following questions:
- Do you know what type of snake or lizard bit you?
What did the snake or lizard look like? How big was the snake or lizard? Did it
rattle?
- When did the bite occur?
- Where were you
bitten?
- How many times were you bitten?
- What are your
main symptoms? How long have you had your symptoms?
- What home
treatment measures have you tried? Did they help?
- What
nonprescription medicines have you tried? Did they help?
- Have you
been treated for a snakebite in the past? If yes, what type of treatment did
you receive?
- What prescription and nonprescription medicine do you
take?
- How long ago was your last
tetanus shot?
- Do you have any
health risks?
Credits
| By | Healthwise Staff |
|---|
| Primary Medical Reviewer | William H. Blahd, Jr., MD, FACEP - Emergency Medicine |
|---|
| Specialist Medical Reviewer | Sean P. Bush, MD, FACEP - Emergency Medicine, Envenomation Specialist |
|---|
| Last Revised | June 6, 2012 |
|---|