How to Tell If You Were Bitten by a Brown Recluse Spider

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The brown recluse spider is known to have a seriously venomous bite. While brown recluse spider bites are extremely rare, people often worry that they've been bitten by one.

This article explains who's at risk of being bitten by a brown recluse, signs that a bite might be from this poisonous spider, and how to treat the wound.

Brown recluse spiders
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Who's at Risk for a Brown Recluse Spider Bite?

Where you live is the biggest factor affecting whether or not there's a chance you'll be bitten by a brown recluse spider. This particular species is found only in the south-central United States, reaching from Texas to Georgia and north to Missouri.

In one study, researchers invited people to send them spider specimens they believed to be brown recluses. Out of a total of 1,773 arachnids submitted from 49 states, 158 different species were identified. From those 29 states where brown recluses are not common, only two brown recluse specimens were identified.

This study found that if you get bitten outside of where brown recluse spiders are known to live, the chances that it came from a brown recluse are nearly zero. It's more likely that the injury was caused by any number of other things, possibly even another species of spider that is less venomous.

For instance, if you were bitten in northern California or Maine, there's almost no chance it's from a brown recluse.

Recluse spiders are called recluse because they do not like to be seen. These night-time, or nocturnal, creatures will not attack people unless they're provoked. The majority of brown recluse bites occur because the spider ended up in the person's clothing.

How to Tell You've Been Bitten by a Brown Recluse

The only way to be sure that a bite came from a brown recluse spider is to see the spider bite you, capture it, and then definitively identify it as a brown recluse.

In reality, though, many people don't even realize they've been bitten at first, so getting a clear look at a spider as it bites you is rare. It's even rarer for someone to be able to capture the spider, but that's the ideal way to identify whether or not a brown recluse has attacked you.

If you're lucky enough to see the spider, look for these telltale traits:

  • Six eyes: These are set in pairs called dyads. One dyad will be up front on a recluse spider, and the other two will be on either side of the head. Most other types of spiders have eight eyes.
  • Furry abdomen: The abdomen is the larger section of the body. On a brown recluse it will have fine hairs and be a solid color.
  • Legs: These are one solid, light color.
  • Body length: Without the legs, this spider is not more than 3/8-inch long.

Brown recluses are also called violin spiders or fiddlebacks. These names refer to a violin-shaped mark on the spider's back. However, it's not always obvious on brown recluses. The pattern appears on other species as well. Look for the other identifying information instead of relying on the violin.

Classifying spiders is difficult, and only an arachnologist (spider expert) can accurately identify a brown recluse for you.

It's unlikely that your doctor will be able to positively identify what type of spider bit you, but you should seek medical attention anyway if you notice a bite getting worse.

Recap

Unless you're in an area where brown recluse spiders are known to live, there is no reason to worry that this species of spider has or will bite you.

If any spider does bite you, it's a good idea to try and capture it so you can identify it. A six-eyed, fuzzy-bodied arachnid with a violin shape on its back could be a brown recluse, but only an expert can tell for sure.

Brown Recluse Bite Symptoms

Most brown recluse bites either don't have any symptoms at all or there is a little swelling with a red bump. Some bites will develop a boil or a pimple. These may appear exactly like an ingrown hair. They might also be mistaken for a skin infection due to Staphylococcus or Streptococcus.

Loxoscelism

The greatest concern regarding brown recluse spiders is that they can lead to a condition called loxoscelism. This is the only known cause of tissue death from a spider, known as necrotic arachnidism.

The name comes from the Loxosceles genus, to which all recluse spiders belong. Tissue death refers to the breakdown of the body's tissue, in this case the skin. The tissue actually dies and cannot be healed. It needs to be cut away. The bite and surrounding area will look like an open wound, called an ulcer, which is the start of necrotic arachnidism.

One extensive review of spider bites notes that tissue death around the bite location can spread within a few days. You might notice skin that is red near the center or boil, then turns white, then blue as it spreads.

In most cases of loxoscelism, the bite is identified by symptoms several hours or days after the fact.

There are very few confirmed deaths from loxoscelism. A 2017 study looked at loxoscelism cases ranging from 1995 through 2005. Of the 57 reported cases of moderate to severe loxoscelism, only two resulted in death. Both individuals—an older man and a young girl—were healthy prior to the bite.

It should also be noted that the study found 373 possible cases of loxoscelism over that 20-year period. The majority resulted in only minor symptoms that cleared up within a few weeks.

Recap

Spider bites, including brown recluse spider bites, usually do not cause serious symptoms. In some cases, though, the venom can lead to a condition in which the skin around the bite begins to die. See a doctor promptly if the wound seems to be getting worse in the hours or days after you're bitten.

Treatment

Most brown recluse bites heal just fine without any medical intervention or first aid. If you see it happen or suspect that you were bitten, the recommended treatment is to use the common first aid technique called RICE.

RICE stands for:

  • Rest
  • Ice
  • Compression
  • Elevation

Wrap the area of the bite with a compression bandage, use ice on it, and elevate it above the level of your heart. All of these measures will reduce swelling and inflammation.

If the bite develops into a boil or an ulcer, see a healthcare provider. This typically is not an emergency situation, but you should have a healthcare provider take a look.

The healthcare provider might take a swab from the boil and culture it to test for bacteria. This will help them determine whether the wound is a spider bite or not.

Testing may identify the wound as a type of skin infection that causes ulcers that look similar to those related to brown recluse bites. Those necrotic skin infections can actually be much more dangerous than a spider bite. But they can be successfully treated with antibiotics, so getting an accurate diagnosis as soon as possible is important.

Summary

If you're in the south-central United States where brown recluse spiders live, you should be aware of what the spiders look like. Unless you see and positively identify a spider that bites you, though, it's impossible to confirm that a bite was caused by a brown recluse. In that case, it's important to watch the area. See a doctor if a boil or ulcers develop or if the wound gets hot, hard, or looks worse.

In rare instances, you may be at risk for loxoscelism, in which the skin around the bite begins to die away. This condition looks similar to bacterial infections that can be treated with antibiotics. Getting a diagnosis as soon as possible can ensure you have the right treatment to stop a potentially life-threatening problem.

A Word From Verywell

Though you may be tempted to worry, rest assured that brown recluse bites are very rare. Follow the recommendation of RICE for first aid and monitor the area you think is a bite. If you notice anything unusual or if boils appear, see your doctor so you can get proper treatment.

Frequently Asked Questions

  • Where do brown recluse spiders live?

    Brown recluse spiders live in the south-central United States. This includes states such as Texas, Oklahoma, Kansas, Iowa, Missouri, Illinois, Arkansas, Indiana, Louisiana, Mississippi, Alabama, and Tennessee.

    The spiders usually are found in dark, enclosed spaces. such as attics, basements, cupboards, boxes, under rocks, and in the bark of dead trees.

  • What are the symptoms of a brown recluse spider bite?

    Symptoms of a brown recluse spider bite include a rash, fever, nausea or vomiting, headache or body aches, and a black ulcer or blister at the bite location. Several hours or even days after the bite, the affected area can develop burning, itching, pain, and redness.

  • How do I treat a brown recluse spider bite?

    Treatment of a brown recluse spider bite will depend on recommendations made by your healthcare provider. They may ask you to perform the following steps.

    • Wash the affected area with soap and water
    • Wrap an ice pack in a towel and apply it to the area
    • Apply an antibiotic lotion or cream to prevent infection.
    • If the bite is on an arm or leg, use the RICE treatment (rest, ice, compression, elevation)

    If the bite develops into a boil or ulcer, see a doctor right away.

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8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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