Main Symptoms

  • Bite from a spider seen on the skin.
  • Onset of bite symptoms (redness, pain, swelling) and a spider is seen in close proximity.

Types of Spider Bites

  1. Black Widow Spider Bite
    • A shiny, jet-black spider with long legs (total size 1 inch).
    • A red (or orange) hourglass-shaped marking on its under-side.
    • Causes immediate local mild pain, swelling and occasionally 2 fang marks.
    • Severe muscle cramps are present by 1 to 6 hours, and last 24 to 48 hours.
    • Rarely causes death (exception: bitten by several spiders or small child is bitten).
    • Note: many are dry bites because the fangs are small.
  2. Brown Recluse Spider Bite
    • A brown spider with long legs (total size 1/2 inch).
    • A dark violin-shaped marking on top of its head.
    • Causes local pain and delayed blister formation in 4 to 8 hours.
    • The center becomes bluish and depressed (crater-like) over 2 to 3 days.
    • Skin damage may require skin grafting in 10% of cases.
    • Systemic symptoms such as fever, vomiting, muscle pain can occur (but no life-threatening symptoms).
  3. Non-dangerous Spider Bites
    • More than 50 spiders in the U.S. have venom and can cause local, nonserious reactions.
    • The bites are painful and mildly swollen for 1 or 2 days (much like a bee sting).
    • Most single, unexplained, tender bites that occur during the night are due to spiders.


Call 911 Now (your child may need an ambulance)If<

  • Difficulty breathing or wheezing

See More Appropriate Topic(instead of this one) If

  • Not a spider bite, see INSECT BITE.


Call Your Doctor Now (night or day) If:

  • Your child looks or acts very sick.

  • Any black widow spider bite.
    FIRST AID for Black Widow Spider Bites:  Apply an ice cube or ice pack to the bite for 20 minutes to reduce the spread of the venom (no tourniquet).
  • Abdominal pain, chest tightness or other muscle cramps.
  • Bite pain is severe.
  • Bite looks infected (red streaking from the bite area, yellow drainage).  (Note: infection doesn't start until at least 24-48 hours after the bite.  Any redness in the first 24 hours is due to venom.)

Call Your Doctor Within 24 Hours (between 9am and 4pm) If:

  • You think your child needs to be seen.
  • Bite starts to look bad (e.g. skin damage, blister or purplish - not just swelling).
  • Bite pain persists for more than 2 days.

Call Your Doctor During Weekday Office Hours If

  • You have other questions or concerns

Parent Care at Home If:

  • Non-serious spider bite and you don't think your child needs to be seen.


  1. Cleansing:  Wash the bite thoroughly with soap and water.
  2. Meat Tenderizer:  Rub the bite area with a cotton ball soaked in a meat tenderizer solution for 20 minutes (Exception: avoid if near the eye).  If not available, apply an ice cube for 20 minutes.
  3. Pain Medicine:  Give acetaminophen (e.g. Tylenol) or ibuprofen as needed for pain.
  4. Expected Course:  Some swelling and pain for 1 to 2 days.  It shouldn't be any worse than a bee sting.
  5. Call Your Doctor If:
    • Severe bite pain persists for more than 2 hours after pain medicine.
    • Abdominal pains or muscle spasms occur.
    • Local pain lasts more than 2 days (48 hours).
    • Bite begins to look infected.
    • Your child becomes worse or develops any of the "Call Your Doctor" symptoms.

Disclaimer: This information is not intended be a substitute for professional medical advice. It is provided for educational purposes only. You assume full responsibility for how you choose to use this information.

Pediatric HouseCalls Online. Copyright © 2000-2004 Barton Schmitt, M.D. FAAP

Reviewed 8/2004

Revised 7/2002

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