Poisoning Due to Brown Spider Venom (Brown Recluse Spider Bites)
A bite from a brown recluse spider can be life threatening. Sweating and chills are two possible symptoms of poisoning by brown spider venom.

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The Brown Recluse Spider

Poisoning due to brown spider venom can be life threatening. The brown recluse is the brown spider associated with these poisonous bites. These bites are common, particularly in warmer climates.

Brown recluse spiders generally have a violin-shaped dark patch just behind their heads. Their generic appearance means that it’s easy to believe that a spider is a brown recluse, even when that is not the case. As a result, brown recluse spider sightings are “widely over-reported,” according to the University of Kentucky College of Agriculture (UK).

This does not mean that you should ignore a bite from a spider that looks like a brown recluse. These bites can be extremely serious. If you believe you have a brown recluse bite, seek medical attention right away.

What Causes a Brown Recluse Spider to Bite?

Brown recluse spiders live in piles of rocks, leaves, logs, wood, and similar substances. If you handle one of these piles without wearing gloves, you might encounter a brown recluse spider. This spider may bite you if it feels threatened.

Brown recluse spiders sometimes live inside people’s homes. They typically hide during the day and come out at night to hunt for insects to eat. If they climb into your shoes or bed, they might bite you when they get stuck there. For example, if you put your foot into a shoe containing a brown recluse spider, or if you roll over on top of one who has climbed into your bed, you may get bitten.

Despite their danger to humans, brown recluse spiders are not aggressive. They will not seek you out to bite you. Instead, they bite only when they feel threatened or trapped.

What Are the Symptoms of Brown Recluse Spider Venom Poisoning?

You generally will not feel a brown recluse spider’s bite. If you do not actually see the spider biting you, you might not even realize that you have been bitten.

Several hours later, however, you will begin to develop symptoms. The area around the bite will start hurting, sometimes very badly. The bite or surrounding area may also become discolored.

A blister will eventually form at the site of the bite. When this bursts, you will find a deep ulcer underneath.

Additional symptoms that you may develop include:

  • fever
  • nausea
  • rash
  • chills
  • listlessness
  • sweating

As scary as a brown recluse bite may sound, these bites are not always terrible. According to the University of Kentucky College of Agriculture, most brown recluse bites can heal within several weeks even without major medical treatment (UK). However, because there is potential for adverse effects, you should always see your doctor if you have a brown recluse bite.

In some cases, the ulcer caused by the bite can persist and grow for weeks. Rarely, the bites can even lead to coma or death. This is more common in children, the elderly, and the severely ill than in healthy adults.

How Brown Recluse Spider Bite is Treated

There is no single course of treatment that all doctors use for a brown recluse bite. There is no effective antivenin (antivenom), as there is for black widows.

If the wound that forms at the bite location becomes infected, you will receive antibiotics to combat that infection.

Depending on where the bite is located, your doctor might put the bitten limb into a sling or a brace.

What Should You Do if You Believe You Have Been Bitten?

Go to the emergency room or seek medical attention immediately if you have been bitten by a brown recluse spider. If possible, capture the spider and take it with you to help your doctor confirm the diagnosis.

Wash the bite as soon as you are bitten.

On your way to the hospital, apply a cold pack for 10 minutes at a time. Leave the pack off for 10 minutes between applications. This helps reduce inflammation and can slow the spread of the venom.

Written by: Gretchen Holm
Edited by:
Medically Reviewed by: George Krucik, MD
Published: Jul 18, 2012
Published By: Healthline Networks, Inc.
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