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Spider Bite

Bite from a spider seen on the skin.
Onset of bite symptoms (redness, pain, swelling) closely following seeing a spider on or near the child.

Types of Spider Bites

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.
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, myalgias (muscle pains) can occur (but no life-threatening symptoms).
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.