Springdale Mason Pediatrics

Spider Bite


  • Bite from a spider

Call or Return If

  • Severe bite pain lasts more than 2 hours after pain medicine
  • Stomach pains or muscle cramps occur
  • Bite pain lasts more than 2 days (48 hours)
  • Bite starts to look infected
  • You think your child needs to be seen
  • Your child becomes worse

About This Topic


  • Redness, pain, swelling of the bite
  • Helpful if spider seen on the skin or around the child

Types of Spider Bites

Minor Spider Bites That Are Not Dangerous

  • More than 50 spiders in the U.S. have venom.
  • Their bites can cause reactions that aren't serious. This includes pain or redness at the bite site.
  • The bites are painful and swollen. This lasts for 1 or 2 days. They can feel and look like a bee sting.
  • Some single, unexplained, tender bites that occur during the night are due to spiders.
  • In the U.S., there are only 2 species of spiders that can cause serious reactions. They are the Black Widow spider and the Brown Recluse spider.

Black Widow Spider Bite

  • A shiny, jet-black spider with long legs (total size 1 inch or 2.5 cm).
  • A red (or orange) hourglass-shaped marking on its under-side.
  • Causes immediate local pain and swelling.
  • Sometimes, you can see 2 fang marks at the bite site.
  • Severe muscle cramps (especially stomach cramps) occur within 1 to 6 hours. These 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.
  • Treatment: Go to ER Now. Reason: Black widow antivenin may be needed.
  • The brown widow spider is related to the black widow. It is found in southern US.
  • Brown widow spider bites are treated the same as black widow bites.

Brown Recluse Spider Bite

  • A brown spider with long legs (total size 1/2 inch or 12 mm).
  • A dark violin shaped marking on top of its head.
  • Causes pain at the bite. Blisters form within 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.
  • Other symptoms such as fever, vomiting, muscle pain can occur. No life-threatening symptoms occur.
  • Brown recluse spiders are hard to identify. If you can, bring the spider along in a jar.

Prevention of Spider Bites

  • Wear gloves when working outdoors.
  • Use an insect repellent. DEET repels spiders as well as insects.
  • The AAP approves DEET use over 2 months old. Use 30% DEET or less. Use 30% DEET if you need 6 hours of protection. Use 10% DEET if you only need protection for 2 hours.
  • Don't put DEET on the hands if your child sucks their thumb or fingers. (Reason: Prevent swallowing DEET)
  • Warn older children who apply their own DEET to use less. A total of 3 or 4 drops can protect the whole body.
  • Put on exposed areas of skin. Do not use near eyes or mouth. Don't use on skin that is covered by clothing. Don't put DEET on sunburns or rashes. (Reason: DEET can be easily absorbed in these areas.)
  • Wash it off with soap and water when your child comes indoors.
  • Caution: DEET can damage clothing made of man-made fibers. It can also damage plastics (eye glasses) and leather. DEET can be used on cotton clothing.

After Care Advice

  • Most spider bites look and feel like a bee sting.
  • They are harmless and go away on their own.
  • The main symptoms are pain and redness.
  • Here is some care advice that should help.
  • Wash the bite well with soap and water.
Cold Pack:
  • For pain or swelling, use a cold pack. You can also use ice wrapped in a wet cloth.
  • Put it on the bite for 20 minutes.
Pain Medicine:
  • To help with the pain, give acetaminophen (such as Tylenol) or ibuprofen. Use as needed.
What to Expect:
  • The swelling and pain lasts for 1 to 2 days.
  • It should not be any worse than a bee sting.

Author: Barton Schmitt MD, FAAP
Copyright 2000-2021 Schmitt Pediatric Guidelines LLC
Disclaimer: This health information is for educational purposes only. You the reader assume full responsibility for how you choose to use it.
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