Spider Bite

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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.