Font Size
A
A
A
2
...

Spider Bite: Brown Recluse Spider Bite (cont.)

Brown Recluse Bite Causes

The brown recluse venom is extremely poisonous, even more potent than that of a rattlesnake. Yet recluse venom causes less disease than a rattlesnake bite because of the small quantities injected into its victims. The venom of the brown recluse is toxic to cells and tissues.

  • This venom is a collection of enzymes. One of the specific enzymes, once released into the victim's skin, causes destruction of local cell membranes, which disrupts the integrity of tissues leading to local breakdown of skin, fat, and blood vessels. This process leads to eventual tissue death (necrosis) in areas immediately surrounding the bite site.
  • The venom also induces in its victim an immune response. The victim's immune system releases inflammatory agents-histamines, cytokines, and interleukins-that recruit signal specific disease-fighting white blood cells to the area of injury. In severe cases, however, these same inflammatory agents can themselves cause injury. These secondary effects of the venom, although extremely rare, can produce these more significant side effects of the spider bite:

What are the symptoms of a brown recluse spider bite?

Brown recluse spider bites often go unnoticed initially because they are usually painless bites. Occasionally, some minor burning that feels like a bee sting is noticed at the time of the bite and a small white blister develops at the site of the bite. Symptoms usually develop two to eight hours after a bite. Keep in mind that most bites cause little tissue destruction.

Victims may experience these symptoms:

Initially the bite site is mildly red and upon close inspection may reveal fang marks. Most commonly, the bite site will become firm and heal with little scaring over the next few days or weeks. Occasionally, the local reaction will be more severe with erythema and blistering, sometimes leading to a blue discoloration, and ultimately leading to a necrotic lesion and scarring. Signs that may be present include:

  • blistering (common),
  • necrosis (death) of skin and subcutaneous fat (less common), and
  • severe destructive necrotic lesions with deep wide borders (rare).
Medically Reviewed by a Doctor on 8/30/2017

Patient Comments & Reviews

The eMedicineHealth doctors ask about Brown Recluse Spider Bite:

Brown Recluse Spider Bite - Treatment

What was the treatment for your brown recluse spider bite?

Brown Recluse Spider Bite - Experience

What was your experience with brown recluse spider bite?

Brown Recluse Spider Bite - Symptoms

What symptoms did you experience with your brown recluse spider bite?


Read What Your Physician is Reading on Medscape

Spider Envenomations: Brown Recluse »

In the United States, reports of severe envenomations by brown spiders began to appear in the late 1800s, and today, in endemic areas, brown spiders continue to be of significant clinical concern.

Read More on Medscape Reference »


Medical Dictionary