Black Widow Spider Bite (Child)

Illustration of a black widow spider

Black widow spiders are black and shiny. They are about a half-inch to 1 inch long. Only female black widows are dangerous. They have a red or orange marking on their bodies. Black widow spiders are found throughout the U.S. But they are most common in the southern and western states. They live in places such as woodpiles, porch furniture, and fences.

Black widow spider bites are rarely life-threatening. But they can be very dangerous to a small child. Common symptoms include:

  • Pain, swelling, numbness, and redness at the bite site

  • Muscle pain

  • Cramping

  • Rigidity in the chest, abdomen, and back

  • Tremors (shaking)

  • Sweating

  • Rapid breathing

  • Weakness

  • Headaches

  • Nausea and vomiting

  • Fast heart rate (in severe cases)

  • High blood pressure (in severe cases)

Symptoms most often appear within 30 minutes to 2 hours of the bite. They may last for 24 to 72 hours.

Antiseptic may be applied to the bite site. Cold packs may ease pain and swelling. Medicine may be given to relieve pain and muscles spasms. A tetanus shot may also be needed. For severe cases, your child may need to stay in the hospital. Antivenom may also be given. This treatment carries risk of allergic reaction. A delayed reaction to the antivenom called serum sickness can also occur 1 to 2 weeks later. This may cause symptoms such as rash, fever and joint pain.

Home care

An antiseptic may be prescribed to put on the bite. Be sure to use it as directed by your child's healthcare provider.

General care

  • Care for the bite site as directed.

  • Let your child rest as needed.

  • Apply cold packs to the bite site to ease pain. Use a cool wet washcloth or crushed ice wrapped in a thin towel. Don't put ice directly on the skin.

  • Watch your child for any signs of allergic reaction or serum sickness if antivenom was given (see below).

  • Check the bite site daily for signs of infection (see below).


  • Caution your child to stay away from woodpiles and other areas that attract spiders.

  • Catch spiders indoors by placing sticky tape on the floor.

  • Hose down outdoor furniture often.

Follow-up care

Follow up with your child’s healthcare provider, or as advised.

When to seek medical advice

Call your child’s healthcare provider right away if any of these occur:

  • Abdominal pain

  • Chest tightness or trouble breathing

  • Muscle pain, cramping, and rigidity

  • Nausea and vomiting

  • Signs of allergic reaction to antivenom such as skin itching, redness, swelling of face or mouth, or problems breathing

  • Signs of serum sickness such as rash, fever or joint pain starting 1 to 2 weeks after treatment

  • Signs of infection at the bite site such as increased redness or streaking, swelling, pain, or foul-smelling drainage

  • Bite site becomes black or blue

  • Bite site won’t heal or gets larger

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